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Sample records for brain imaging agents

  1. Design of brain imaging agents for positron emission tomography: do large bioconjugates provide an opportunity for in vivo brain imaging?

    Science.gov (United States)

    Schirrmacher, Ralf; Bernard-Gauthier, Vadim; Reader, Andrew; Soucy, Jean-Paul; Schirrmacher, Esther; Wängler, Björn; Wängler, Carmen

    2013-09-01

    The development of brain imaging agents for positron emission tomography and other in vivo imaging modalities mostly relies on small compounds of low MW as a result of the restricted transport of larger molecules, such as peptides and proteins, across the blood-brain barrier. Besides passive transport, only a few active carrier mechanisms, such as glucose transporters and amino acid transporters, have so far been exploited to mediate the accumulation of imaging probes in the brain. An important question for the future is whether some of the abundant active carrier systems located at the blood-brain barrier can be used to shuttle potential, but non-crossing, imaging agents into the brain. What are the biological and chemical constrictions toward such bioconjugates and is it worthwhile to persue such a delivery strategy?

  2. Solvation effects on brain uptakes of isomers of 99mTc brain imaging agents

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Analysis of electrostatic hydration free energies of the isomers of the 99mTc-BAT and 99mTc-DADT complexes is carried out using the computer simulation technique. The results show that not only a correlation exists between the logarithm of the brain uptake and the electrostatic hydration free energy for the isomers of 99mTc-brain radiopharmaceuticals, but also a linear relationship exists between the logarithm of the ratio of the brain uptake of the syn isomer to that of the anti one and the difference between the electrostatic hydration free energy of the syn-isomer and that of the anti one. Furthermore, the investigation on the important factors influencing the brain uptakes of 99mTc-radiopharmaceuticals and the reasons of the different biodistribution of the isomers of the 99mTc-complexes is explored at the molecular level. The results may provide a reference for the rational drug design of brain imaging agents.

  3. Potential new approaches for the development of brain imaging agents for single-photon applications

    Energy Technology Data Exchange (ETDEWEB)

    Knapp, F.F. Jr.; Srivastava, P.C.

    1984-01-01

    This paper describes new strategies for the brain-specific delivery of radionuclides that can be used to evaluate regional cerebral perfusion by single photon imaging techniques. A description of several examples of interesting new strategies that have recently been reported is presented. A new approach at this institution for the brain-specific delivery of radioiodinated iodophenylalkyl-substituted dihyronicotinamide systems is described which shows good brain uptake and retention in preliminary studies in rats. Following transport into the brain these agents appear to undergo facile intracerebral oxidation to the quaternized analogues which do not recross the intact blood-brain barrier and so are effectively trapped in the brain. 49 refs., 9 figs., 1 tab.

  4. Targeting Potassium Channels for Increasing Delivery of Imaging Agents and Therapeutics to Brain Tumors

    Directory of Open Access Journals (Sweden)

    Nagendra Sanyasihally Ningaraj

    2013-05-01

    Full Text Available Every year in the US, 20,000 new primary and nearly 200,000 metastatic brain tumor cases are reported. The cerebral microvessels/ capillaries that form the blood–brain barrier (BBB not only protect the brain from toxic agents in the blood but also pose a significant hindrance to the delivery of small and large therapeutic molecules. Different strategies have been employed to circumvent the physiological barrier posed by blood-brain tumor barrier (BTB. Studies in our laboratory have identified significant differences in the expression levels of certain genes and proteins between normal and brain tumor capillary endothelial cells. In this study, we validated the non-invasive and clinically relevant Dynamic Contrast Enhancing-Magnetic Resonance Imaging (DCE-MRI method with invasive, clinically irrelevant but highly accurate Quantitative Autoradiography (QAR method using rat glioma model. We also showed that DCE-MRI metric of tissue vessel perfusion-permeability is sensitive to changes in blood vessel permeability following administration of calcium-activated potassium (BKCa channel activator NS-1619. Our results show that human gliomas and brain tumor endothelial cells that overexpress BKCa channels can be targeted for increased BTB permeability for MRI enhancing agents to brain tumors. We conclude that monitoring the outcome of increased MRI enhancing agents’ delivery to microsatellites and leading tumor edges in glioma patients would lead to beneficial clinical outcome.

  5. Preparation of new technetium-99m NNS/X complexes and selection for brain imaging agent

    Institute of Scientific and Technical Information of China (English)

    HE Qiange; CHEN Xiangji; MIAO Yubin; LIU Boli

    2004-01-01

    Based on excellent experiment results of 99mTcO-MPBDA-Cl, two new ligands MPTDA and MPDAA are synthesized. Then series of 99mTcO3+ complexes are prepared through adding different halide anions, followed by tests of physical chemistry qualities and biodistribution experiments. And results of these experiments show that complexes formed with MPTDA and MPDAA have better lipophilicity than those formed with MPBDA, still maintain the good brain retention ability of this type of compounds, but radioactivity uptake in blood is higher than that of 99mTcO-MPBDA and ratios of brain/blood are reduced. Obvious affections are fetched out on brain uptake and retention if fluoride, bromide or iodide anions are added. Results of experiments can be explained in reason with theoretic computation. It is confirmed that 99mTcO-MPBDA-Cl has potential to develop a new type of brain imaging agent considering integrated factors such as brain uptake, retention and toxicity.

  6. F-18 Polyethyleneglycol stilbenes as PET imaging agents targeting A{beta} aggregates in the brain

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Wei [Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104 (United States); Oya, Shunichi [Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104 (United States); Kung Meiping [Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104 (United States); Hou, Catherine [Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104 (United States); Maier, Donna L. [Department of Neuroscience, AstraZeneca, Wilmington, DE 19850 (United States); Kung, Hank F. [Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104 (United States) and Department of Pharmacology, University of Pennsylvania, Philadelphia, PA 19104 (United States)]. E-mail: kunghf@sunmac.spect.upenn.edu

    2005-11-01

    This paper describes a novel series of {sup 18}F-labeled polyethyleneglycol (PEG)-stilbene derivatives as potential {beta}-amyloid (A{beta}) plaque-specific imaging agents for positron emission tomography (PET). In these series of compounds, {sup 18}F is linked to the stilbene through a PEG chain, of which the number of ethoxy groups ranges from 2 to 5. The purpose of adding PEG groups is to lower the lipophilicity and improve bioavailability. The syntheses of the 'cold' compounds and the {sup 18}F-labeled PEG stilbene derivatives are successfully achieved. All of the fluorinated stilbenes displayed high binding affinities in an assay using postmortem AD brain homogenates (K {sub i}=2.9-6.7 nM). Labeling was successfully performed by a substitution of the mesylate group of 10a-d by [{sup 18}F]fluoride giving the target compounds [{sup 18}F]12a-d (EOS, specific activity, 900-1500 Ci/mmol; radiochemical purity >99%). In vivo biodistribution of these novel {sup 18}F ligands in normal mice exhibited excellent brain penetrations and rapid washouts after an intravenous injection (6.6-8.1 and 1.2-2.6% dose/g at 2 and 60 min, respectively). Autoradiography of postmortem AD brain sections of [{sup 18}F]12a-d confirmed the specific binding related to the presence of A{beta} plaques. In addition, in vivo plaque labeling can be clearly demonstrated with these {sup 18}F-labeled agents in transgenic mice (Tg2576), a useful animal model for Alzheimer's disease. In conclusion, the preliminary results strongly suggest these fluorinated PEG stilbene derivatives are suitable candidates as A{beta} plaque imaging agents for studying patients with Alzheimer's disease.

  7. Uncertainty analysis for absorbed dose from a brain receptor imaging agent

    Energy Technology Data Exchange (ETDEWEB)

    Aydogan, B.; Miller, L.F. [Univ. of Tennessee, Knoxville, TN (United States). Nuclear Engineering Dept.; Sparks, R.B. [Oak Ridge Inst. for Science and Education, TN (United States); Stubbs, J.B. [Radiation Dosimetry Systems of Oak Ridge, Inc., Knoxville, TN (United States)

    1999-01-01

    Absorbed dose estimates are known to contain uncertainties. A recent literature search indicates that prior to this study no rigorous investigation of uncertainty associated with absorbed dose has been undertaken. A method of uncertainty analysis for absorbed dose calculations has been developed and implemented for the brain receptor imaging agent {sup 123}I-IPT. The two major sources of uncertainty considered were the uncertainty associated with the determination of residence time and that associated with the determination of the S values. There are many sources of uncertainty in the determination of the S values, but only the inter-patient organ mass variation was considered in this work. The absorbed dose uncertainties were determined for lung, liver, heart and brain. Ninety-five percent confidence intervals of the organ absorbed dose distributions for each patient and for a seven-patient population group were determined by the ``Latin Hypercube Sampling`` method. For an individual patient, the upper bound of the 95% confidence interval of the absorbed dose was found to be about 2.5 times larger than the estimated mean absorbed dose. For the seven-patient population the upper bound of the 95% confidence interval of the absorbed dose distribution was around 45% more than the estimated population mean. For example, the 95% confidence interval of the population liver dose distribution was found to be between 1.49E+0.7 Gy/MBq and 4.65E+07 Gy/MBq with a mean of 2.52E+07 Gy/MBq. This study concluded that patients in a population receiving {sup 123}I-IPT could receive absorbed doses as much as twice as large as the standard estimated absorbed dose due to these uncertainties.

  8. Synthesis and tissue distribution of substituted [{sup 125}I]iodophenylamine derivatives: Possible brain imaging agents

    Energy Technology Data Exchange (ETDEWEB)

    Ghaffari, M.A.; Ali, H.; Rousseau, J.; Lier, J.E. van

    1997-02-01

    The synthesis and brain uptake in mice of the radioidinated derivatives of N,N-dimethyl-N'-(idodimethoxyphenyl)-1,3-propanediamine, as well as the N-substituted derivatives of (iodoalkylphenyl)isopropyl, iodoalkylphenylethylamine and 3,4-(methylenedioxy)phenyl-amphetamine (MDA) are described. These compounds contain structural features of both IMP and HIPDM, the cerebral perfusion agents currently in clinical use. The radiolabeled analogs were obtained via the [{sup 125}I]I exchange method, or by [{sup 125}I]NaI treatment of the iodo-free precursor in the presence of an oxidant. Following intravenous injection in mice, all compounds showed important radioactivity concentrations in the lungs and kidneys. The N-substituted (iodoalkylphenyl)isopropyl and iodoalkylphenyl-ethylamine derivatives displayed a high initial brain uptake (>10%IDg{sup -1}) followed by a rapid clearance phase, resulting in lower brain-to-blood ratios as those reported for IMP and HIPDM. In contrast, N,N-dimethyl-N'-(iododimethoxyphenyl)-1,3-propanediamine derivatives featuring the iodo substituent on the benzene carbon adjacent to the methyl amine group and the methoxy substituents on the 2,5- or 2,4-positions, showed low but more persistant brain uptake. Combined with fast blood clearance, this resulted in high brain-to-blood ratios at later time points. Among all compounds tested, the highest brain-to-blood ratio was observed with compound N,N-dimethyl-N'-(6-iodo-3,4-dimethoxyphenyl)-1,3-propanediamine (27e), reaching a maximum of >20 at 12 h post-injection.

  9. Design, synthesis and evaluation of redox radiopharmaceuticals: a potential new approach for the development of brain imaging agents

    Energy Technology Data Exchange (ETDEWEB)

    Srivastava, P.C.; Knapp, F.F. Jr.

    1986-01-01

    The fabrication and complete evaluation are described of a dihydropyridine in equilibrium pyridinium salt type redox system for the delivery of radioiodinated agents to the brain. The pivotal intermediate, N-succinimidyl (1-methylpyridinium iodide)-3-carboxylate was prepared by condensation of nicotinic acid and N-hydroxysuccinimide in the presence of dicyclohexylcarbodimide, followed by quaternization of III with methyl iodide. Tissue distribution studies of /sup 125/I-labeled 4-iodoaniline and the redox agents were performed in rats. (/sup 125/I)Iodoaniline initially showed moderate (0.58% dose/gm) brain uptake with subsequent release of the radioactivity from the brain. (/sup 125/I)Iodoaniline, when coupled to a dihydropyridine carrier showed higher uptake and retention in the brain. The (/sup 125/I)iodophenylethyl analogue showed uptake and retention in the brain to be very similar. Apparently the lipophilic agents cross the blood-brain barrier and are oxidized (quaternized) within the brain. The blood-brain barrier then prevents their release resulting in high uptake and retention in the brain and high brain:blood ratios. 11 refs., 3 figs.

  10. Design, synthesis and evaluation of 2-deoxy-2-iodovinyl-branched carbohydrates as potential brain imaging agents

    Energy Technology Data Exchange (ETDEWEB)

    Goodman, M.M.; Callahan, A.P.; Knapp, F.F. Jr.

    1986-01-01

    Radioiodinated carbohydrates such as 2-deoxy-2-iodo-D-glucose and 3-deoxy-3-iodo-D-glucose undergo facile chemical or in vivo deiodination which precludes their use as radiotracers of glucose metabolism in tissues. To overcome the problems resulting from in vivo deiodination, we explored the concept of stabilizing radioiodide on a model carbohydrate, (E)-C-3-iodovinyl-D-allose (10) as an iodovinyl moiety. This agent did not exhibit brain specificity but showed low in vivo deiodination which demonstrated for the first time that radioiodide can be stabilized on a carbohydrate. The goal of this study was to develop a deoxy-branched carbohydrate with radioiodide stabilized as a vinyliodide with the objective of achieving high brain uptake. 10 refs., 1 fig., 1 tab.

  11. Folic acid-conjugated MnO nanoparticles as a T1 contrast agent for magnetic resonance imaging of tiny brain gliomas.

    Science.gov (United States)

    Chen, Ning; Shao, Chen; Qu, Yanming; Li, Shuai; Gu, Wei; Zheng, Tingting; Ye, Ling; Yu, Chunjiang

    2014-11-26

    Detection of brain gliomas at the earliest stage is of great importance to improve outcomes, but it remains a most challenging task. In this study, oleic acid capped manganese oxide (MnO) nanoparticles (NPs) were prepared by the thermal decomposition of manganese oleate precursors and then transformed to water-dispersible MnO NPs by replacing oleic acid with N-(trimethoxysilylpropyl) ethylene diamine triacetic acid (TETT) silane. The covalently bonded TETT silane offers MnO NPs colloidal stability and abundant carboxylic functional groups allowing the further conjugation of the glioma-specific moiety, folic acid (FA). Moreover, the thin layer of TETT silane ensures a short distance between external Mn ion and water proton, which endows the FA-conjugated, TETT modified MnO (MnO-TETT-FA) NPs a longitudinal relaxivity as high as 4.83 mM(-1) s(-1). Accordingly, the in vivo magnetic resonance (MR) images demonstrated that MnO-TETT-FA NPs could efficiently enhance the MRI contrast for tiny brain gliomas. More importantly, due to the specificity of FA, MnO-TETT-FA NPs led to a clearer margin of the tiny glioma. This together with the good biocompatibility discloses the great potential of MnO-TETT-FA NPs as effective MRI contrast agents for the early diagnosis of brain gliomas.

  12. Brain Image Motion Correction

    DEFF Research Database (Denmark)

    Jensen, Rasmus Ramsbøl; Benjaminsen, Claus; Larsen, Rasmus

    2015-01-01

    The application of motion tracking is wide, including: industrial production lines, motion interaction in gaming, computer-aided surgery and motion correction in medical brain imaging. Several devices for motion tracking exist using a variety of different methodologies. In order to use such devices...... offset and tracking noise in medical brain imaging. The data are generated from a phantom mounted on a rotary stage and have been collected using a Siemens High Resolution Research Tomograph for positron emission tomography. During acquisition the phantom was tracked with our latest tracking prototype...

  13. MRI brain imaging.

    Science.gov (United States)

    Skinner, Sarah

    2013-11-01

    General practitioners (GPs) are expected to be allowed to request MRI scans for adults for selected clinically appropriate indications from November 2013 as part of the expansion of Medicare-funded MRI services announced by the Federal Government in 2011. This article aims to give a brief overview of MRI brain imaging relevant to GPs, which will facilitate explanation of scan findings and management planning with their patients. Basic imaging techniques, common findings and terminology are presented using some illustrative case examples.

  14. Subharmonic imaging of contrast agents.

    Science.gov (United States)

    Forsberg, F; Shi, W T; Goldberg, B B

    2000-03-01

    Ultrasound contrast agents promise to improve the sensitivity and specificity of diagnostic ultrasound imaging. It is of great importance to adapt ultrasound equipment for optimal use with contrast agents e.g., by exploiting the nonlinear properties of the contrast microbubbles. Harmonic imaging is one technique that has been extensively studied and is commercially available. However, harmonic imaging is associated with problems, due to second harmonic generation and accumulation within the tissue itself. Given the lack of subharmonic generation in tissue, one alternative is the creation of subharmonic images by transmitting at the fundamental frequency (fo) and receiving at the subharmonic (fo/2). Subharmonic imaging should have a much better lateral resolution and may be suitable for scanning deep-lying structures owing to the higher transmit frequency and the much smaller attenuation of scattered subharmonic signals. In this paper, we will review different aspects of subharmonic imaging including implementation, in-vitro gray-scale imaging and subharmonic aided pressure estimation.

  15. Perfusion harmonic imaging of the human brain

    Science.gov (United States)

    Metzler, Volker H.; Seidel, Guenter; Wiesmann, Martin; Meyer, Karsten; Aach, Til

    2003-05-01

    The fast visualisation of cerebral microcirculation supports diagnosis of acute cerebrovascular diseases. However, the commonly used CT/MRI-based methods are time consuming and, moreover, costly. Therefore we propose an alternative approach to brain perfusion imaging by means of ultrasonography. In spite of the low signal/noise-ratio of transcranial ultrasound and the high impedance of the skull, flow images of cerebral blood flow can be derived by capturing the kinetics of appropriate contrast agents by harmonic ultrasound image sequences. In this paper we propose three different methods for human brain perfusion imaging, each of which yielding flow images indicating the status of the patient's cerebral microcirculation by visualising local flow parameters. Bolus harmonic imaging (BHI) displays the flow kinetics of bolus injections, while replenishment (RHI) and diminution harmonic imaging (DHI) compute flow characteristics from contrast agent continuous infusions. RHI measures the contrast agents kinetics in the influx phase and DHI displays the diminution kinetics of the contrast agent acquired from the decay phase. In clinical studies, BHI- and RHI-parameter images were found to represent comprehensive and reproducible distributions of physiological cerebral blood flow. For DHI it is shown, that bubble destruction and hence perfusion phenomena principally can be displayed. Generally, perfusion harmonic imaging enables reliable and fast bedside imaging of human brain perfusion. Due to its cost efficiency it complements cerebrovascular diagnostics by established CT/MRI-based methods.

  16. Whole-body biodistribution and brain PET imaging with [{sup 18}F]AV-45, a novel amyloid imaging agent - a pilot study

    Energy Technology Data Exchange (ETDEWEB)

    Lin, K.-J. [Department of Nuclear Medicine and Molecular Imaging Center, Chang Gung Memorial Hospital, Taiwan (China); Department of Medical Imaging and Radiological Sciences, Chang Gung University, Taiwan (China); Hsu, W.-C. [Department of Neurology, Chang Gung Memorial Hospital, Taiwan (China); Hsiao, I.-T.; Wey, S.-P. [Department of Nuclear Medicine and Molecular Imaging Center, Chang Gung Memorial Hospital, Taiwan (China); Department of Medical Imaging and Radiological Sciences, Chang Gung University, Taiwan (China); Jin, L.-W. [M.I.N.D. Institute and Department of Pathology, University of California, Davis, CA (United States); Skovronsky, Daniel [Avid Radiopharmaceuticals, Inc., Philadelphia, PA (United States); Wai, Y.-Y. [Department of Nuclear Medicine and Molecular Imaging Center, Chang Gung Memorial Hospital, Taiwan (China); Department of Radiology, Chang Gung Memorial Hospital, Taiwan (China); Chang, H.-P.; Lo, C.-W.; Yao, C.H.; Yen, T.-C. [Department of Nuclear Medicine and Molecular Imaging Center, Chang Gung Memorial Hospital, Taiwan (China); Kung, M.-P. [Department of Nuclear Medicine and Molecular Imaging Center, Chang Gung Memorial Hospital, Taiwan (China); Department of Radiology, University of Pennsylvania, Philadelphia, PA (United States)

    2010-05-15

    Purpose: The compound (E)-4-(2-(6-(2-(2-(2-{sup 18}F-fluoroethoxy)ethoxy)ethoxy) pyridin-3-yl)vinyl)-N-methylbenzenamine ([{sup 18}F]AV-45) is a novel radiopharmaceutical capable of selectively binding to {beta}-amyloid (A{beta}) plaques. This pilot study reports the safety, biodistribution, and radiation dosimetry of [{sup 18}F]AV-45 in human subjects. Methods: In vitro autoradiography and fluorescent staining of postmortem brain tissue from patients with Alzheimer's disease (AD) and cognitively healthy subjects were performed to assess the specificity of the tracer. Biodistribution was assessed in three healthy elderly subjects (mean age: 60.0{+-}5.2 years) who underwent 3-h whole-body positron emission tomography (PET)/computed tomographic (CT) scans after a bolus injection of 381.9{+-}13.9 MBq of [{sup 18}F]AV-45. Another six subjects (three AD patients and three healthy controls, mean age: 67.7{+-}13.6 years) underwent brain PET studies. Source organs were delineated on PET/CT. All subjects underwent magnetic resonance imaging (MRI) for obtaining structural information. Results: In vitro autoradiography revealed exquisitely high specific binding of [{sup 18}F]AV-45 to postmortem AD brain sections, but not to the control sections. There were no serious adverse events throughout the study period. The peak uptake of the tracer in the brain was 5.12{+-}0.41% of the injected dose. The highest absorbed organ dose was to the gallbladder wall (184.7{+-}78.6 {mu}Gy/MBq, 4.8 h voiding interval). The effective dose equivalent and effective dose values for [{sup 18}F]AV-45 were 33.8{+-}3.4 {mu}Sv/MBq and 19.3{+-}1.3 {mu}Sv/MBq, respectively. Conclusion: [{sup 18}F]AV-45 binds specifically to A{beta} in vitro, and is a safe PET tracer for studying A{beta} distribution in human brain. The dosimetry is suitable for clinical and research application.

  17. Brain hypoxia imaging

    Energy Technology Data Exchange (ETDEWEB)

    Song, Ho Chun [Chonnam National University Medical School, Gwangju (Korea, Republic of)

    2007-04-15

    The measurement of pathologically low levels of tissue pO{sub 2} is an important diagnostic goal for determining the prognosis of many clinically important diseases including cardiovascular insufficiency, stroke and cancer. The target tissues nowadays have mostly been tumors or the myocardium, with less attention centered on the brain. Radiolabelled nitroimidazole or derivatives may be useful in identifying the hypoxic cells in cerebrovascular disease or traumatic brain injury, and hypoxic-ischemic encephalopathy. In acute stroke, the target of therapy is the severely hypoxic but salvageable tissue. {sup 18}F-MISO PET and {sup 99m}Tc-EC-metronidazole SPECT in patients with acute ischemic stroke identified hypoxic tissues and ischemic penumbra, and predicted its outcome. A study using {sup 123}I-IAZA in patient with closed head injury detected the hypoxic tissues after head injury. Up till now these radiopharmaceuticals have drawbacks due to its relatively low concentration with hypoxic tissues associated with/without low blood-brain barrier permeability and the necessity to wait a long time to achieve acceptable target to background ratios for imaging in acute ischemic stroke. It is needed to develop new hypoxic marker exhibiting more rapid localization in the hypoxic region in the brain. And then, the hypoxic brain imaging with imidazoles or non-imidazoles may be very useful in detecting the hypoxic tissues, determining therapeutic strategies and developing therapeutic drugs in several neurological disease, especially, in acute ischemic stroke.

  18. Deep two-photon microscopic imaging through brain tissue using the second singlet state from fluorescent agent chlorophyll α in spinach leaf.

    Science.gov (United States)

    Shi, Lingyan; Rodríguez-Contreras, Adrián; Budansky, Yury; Pu, Yang; Nguyen, Thien An; Alfano, Robert R

    2014-06-01

    Two-photon (2P) excitation of the second singlet (S₂) state was studied to achieve deep optical microscopic imaging in brain tissue when both the excitation (800 nm) and emission (685 nm) wavelengths lie in the "tissue optical window" (650 to 950 nm). S₂ state technique was used to investigate chlorophyll α (Chl α) fluorescence inside a spinach leaf under a thick layer of freshly sliced rat brain tissue in combination with 2P microscopic imaging. Strong emission at the peak wavelength of 685 nm under the 2P S₂ state of Chl α enabled the imaging depth up to 450 μm through rat brain tissue.

  19. Brain imaging and autism

    Energy Technology Data Exchange (ETDEWEB)

    Zilbovicius, M. [Service Hospitalier Frederic Joliot (CEA/DSV/DRM), INSERM CEA 0205, 91 - Orsay (France)

    2006-07-01

    Autism is a neuro-developmental disorder with a range of clinical presentations, from mild to severe, referred to as autism spectrum disorders (ASD). The most common clinical ASD sign is social interaction impairment, which is associated with verbal and non-verbal communication deficits and stereotyped and obsessive behaviors. Thanks to recent brain imaging studies, scientists are getting a better idea of the neural circuits involved in ASD. Indeed, functional brain imaging, such as positron emission tomography (PET), single positron emission tomograph y (SPECT) and functional MRI (fMRI) have opened a new perspective to study normal and pathological brain functions. Three independent studies have found anatomical and rest functional temporal abnormalities. These anomalies are localized in the superior temporal sulcus bilaterally which are critical for perception of key social stimuli. In addition, functional studies have shown hypo-activation of most areas implicated in social perception (face and voice perception) and social cognition (theory of mind). These data suggest an abnormal functioning of the social brain network. The understanding of such crucial abnormal mechanism may drive the elaboration of new and more adequate social re-educative strategies in autism. (author)

  20. Synthesis and tissue distribution of four Se-labeled tertiary amines, potential brain pH imaging agents.

    Science.gov (United States)

    Plenevaux, A; Cantineau, R; Brihaye, C; Lemaire, C; Christiaens, L; Guillaume, M

    1990-01-01

    Four new tertiary amines: bis(3-N,N-dimethyl aminopropyl)selenide (PROMOSE), bis(3-N-(morpholino)propyl)selenide, N-methyl-selenomorpholine and N-phenyl-selenomorpholine structurally related to MOSE proposed by Kung and Blau, have been labeled through a radiochemical procedure suitable for both 75Se and 73Se. The radiochemical yields of the carrier added synthesis ranged between 64 and 85% for the four 75Se labelings and was 64% EOB time corrected for [73Se]PROMOSE. The chemical and radiochemical purities were higher than 99% after chromatographic purifications. The n-octanol/phosphate buffer partition coefficients (P) were measured at various pH (6.5-8) for each compound and the tissue distributions of PROMOSE in rats were also carried out. The experimental results showed a good correlation between the P = f(pH) function and the in vivo behaviour of the considered compound. PROMOSE was selected for further investigations as a brain pH indicator.

  1. Quantitative assessment of brain perfusion with magnetic resonance imaging

    NARCIS (Netherlands)

    Bleeker, Egbert Jan Willem

    2011-01-01

    This thesis focuses on assessing blood supply to brain tissue using MRI. For Dynamic Susceptibility Contrast-MRI a series of images is acquired during the passage of a bolus contrast agent through the brain up to the point that the contrast agent is equally mixed within the total blood pool. The tis

  2. Imaging brain plasticity after trauma

    Institute of Scientific and Technical Information of China (English)

    Zhifeng Kou; Armin Iraji

    2014-01-01

    The brain is highly plastic after stroke or epilepsy;however, there is a paucity of brain plasticity investigation after traumatic brain injury (TBI). This mini review summarizes the most recent evidence of brain plasticity in human TBI patients from the perspective of advanced magnetic resonance imaging. Similar to other forms of acquired brain injury, TBI patients also demonstrat-ed both structural reorganization as well as functional compensation by the recruitment of other brain regions. However, the large scale brain network alterations after TBI are still unknown, and the ifeld is still short of proper means on how to guide the choice of TBI rehabilitation or treat-ment plan to promote brain plasticity. The authors also point out the new direction of brain plas-ticity investigation.

  3. [11C]SMe-ADAM, an imaging agent for the brain serotonin transporter: synthesis, pharmacological characterization and microPET studies in rats.

    Science.gov (United States)

    Zessin, Jörg; Deuther-Conrad, Winnie; Kretzschmar, Marion; Wüst, Frank; Pawelke, Beate; Brust, Peter; Steinbach, Jörg; Bergmann, Ralf

    2006-01-01

    N,N-Dimethyl-2-(2-amino-4-methylthiophenylthio)benzylamine (SMe-ADAM, 1) is a highly potent and selective inhibitor of the serotonin transporter (SERT). This compound was labeled with carbon-11 by methylation of the S-desmethyl precursor 10 with [(11)C]methyl iodide to obtain the potential positron emission tomography (PET) radioligand [(11)C]SMe-ADAM. The radiochemical yield was 27 +/- 5%, and the specific radioactivity was 26-40 GBq/micromol at the end of synthesis. Ex vivo and in vivo biodistribution experiments in rats demonstrated a rapid accumulation of the radiotracer in brain regions known to be rich in SERT, such as the thalamus/hypothalamus region (3.59 +/- 0.41%ID/g at 5 min after injection). The specific uptake reached a thalamus to cerebellum ratio of 6.74 +/- 0.95 at 60 min postinjection. The [(11)C]SMe-ADAM uptake in the thalamus was significantly decreased by pretreatment with fluoxetine to 38 +/- 11% of the control value. Furthermore, no metabolites of [(11)C]SMe-ADAM could be detected in the SERT-rich regions of the rat brain. It is concluded that [(11)C]SMe-ADAM may be a suitable PET ligand for SERT imaging in the living brain.

  4. Stereoselective synthesis and biological evaluation of syn-1-amino-3-[18F]fluorocyclobutyl-1-carboxylic acid as a potential positron emission tomography brain tumor imaging agent.

    Science.gov (United States)

    Yu, Weiping; Williams, Larry; Camp, Vernon M; Malveaux, Eugene; Olson, Jeffrey J; Goodman, Mark M

    2009-03-01

    Amino acid syn-1-amino-3-fluoro-cyclobutyl-1-carboxylic acid (syn-FACBC) 12, the isomer of anti-FACBC, has been selectively synthesized and [(18)F] radiofluorinated in 52% decay-corrected yield using no-carrier-added [(18)F]fluoride. The key step in the synthesis of the desired isomer involved stereoselective reduction using lithium alkylborohydride/zinc chloride, which improved the ratio of anti-alcohol to syn-alcohol from 17:83 to 97:3. syn-FACBC 12 entered rat 9L gliosarcoma cells primarily via L-type amino acid transport in vitro with high uptake of 16% injected dose per 5 x 10(5) cells. Biodistribution studies in rats with 9L gliosarcoma brain tumors demonstrated high tumor to brain ratio of 12:1 at 30 min post injection. In this model, amino acid syn-[(18)F]FACBC 12 is a promising metabolically based radiotracer for positron emission tomography brain tumor imaging.

  5. [{sup 11}C]SMe-ADAM, an imaging agent for the brain serotonin transporter: synthesis, pharmacological characterization and microPET studies in rats

    Energy Technology Data Exchange (ETDEWEB)

    Zessin, Joerg [Institut fuer Bioanorganische und Radiopharmazeutische Chemie, Forschungszentrum Rossendorf, 01314 Dresden (Germany)]. E-mail: j.zessin@fz-rossendorf.de; Deuther-Conrad, Winnie [Institut fuer Interdisziplinaere Isotopenforschung, 04318 Leipzig (Germany); Kretzschmar, Marion [Institut fuer Bioanorganische und Radiopharmazeutische Chemie, Forschungszentrum Rossendorf, 01314 Dresden (Germany); Wuest, Frank [Institut fuer Bioanorganische und Radiopharmazeutische Chemie, Forschungszentrum Rossendorf, 01314 Dresden (Germany); Pawelke, Beate [Institut fuer Bioanorganische und Radiopharmazeutische Chemie, Forschungszentrum Rossendorf, 01314 Dresden (Germany); Brust, Peter [Institut fuer Interdisziplinaere Isotopenforschung, 04318 Leipzig (Germany); Steinbach, Joerg [Institut fuer Interdisziplinaere Isotopenforschung, 04318 Leipzig (Germany); Bergmann, Ralf [Institut fuer Bioanorganische und Radiopharmazeutische Chemie, Forschungszentrum Rossendorf, 01314 Dresden (Germany)

    2006-01-15

    N,N-Dimethyl-2-(2-amino-4-methylthiophenylthio)benzylamine (S Me-Adam, 1) is a highly potent and selective inhibitor of the serotonin transporter (SPERT). This compound was labeled with carbon-11 by methylation of the S-desmethyl precursor 10 with [{sup 11}C]methyl iodide to obtain the potential positron emission tomography (PET) radioligand [{sup 11}C]S Me-Adam. The radiochemical yield was 27{+-}5%, and the specific radioactivity was 26-40 GBq/{mu}mol at the end of synthesis. Ex vivo and in vivo biodistribution experiments in rats demonstrated a rapid accumulation of the radiotracer in brain regions known to be rich in SPERT, such as the thalamus/hypothalamus region (3.59{+-}0.41%ID/g at 5 min after injection). The specific uptake reached a thalamus to cerebellum ratio of 6.74{+-}0.95 at 60 min postinjection. The [{sup 11}C]SMe-ADAM uptake in the thalamus was significantly decreased by pretreatment with fluoxetine to 38{+-}11% of the control value. Furthermore, no metabolites of [{sup 11}C]SMe-ADAM could be detected in the SERT-rich regions of the rat brain. It is concluded that [{sup 11}C]SMe-ADAM may be a suitable PET ligand for SERT imaging in the living brain.

  6. Agents described in the Molecular Imaging and Contrast Agent Database for imaging carbonic anhydrase IX expression.

    Science.gov (United States)

    Sneddon, Deborah; Poulsen, Sally-Ann

    2014-10-01

    Carbonic anhydrase IX (CA IX) is selectively expressed in a range of hypoxic tumours and is a validated endogenous hypoxia marker with prognostic significance; hence, CA IX is of great interest as a molecular imaging target in oncology. In this review, we present an overview of the different imaging agents and imaging modalities that have been applied for the in vivo detection of CA IX. The imaging agents reviewed are all entries in the Molecular Imaging and Contrast Agent Database (MICAD) and comprise antibody, antibody fragments and small molecule imaging agents. The effectiveness of these agents for imaging CA IX in vivo gave variable performance; however, a number of agents proved very capable. As molecular imaging has become indispensable in current medical practice we anticipate that the clinical significance of CA IX will see continued development and improvements in imaging agents for targeting this enzyme.

  7. Targeted Agents for Imaging and Therapy

    NARCIS (Netherlands)

    Grüll, H.; Robillard, M.S.

    2005-01-01

    Molecular Imaging allows the visualization of biological processesin vivo, offering new chances for healthcare with respect to early diagnosis and improved therapy. The new field of molecular imaging isboosted by more sensitive imaging systems and the emergence of targeted imaging agents that hom

  8. Brain image Compression, a brief survey

    Directory of Open Access Journals (Sweden)

    Saleha Masood

    2013-01-01

    Full Text Available Brain image compression is known as a subfield of image compression. It allows the deep analysis and measurements of brain images in different modes. Brain images are compressed to analyze and diagnose in an effective manner while reducing the image storage space. This survey study describes the different existing techniques regarding brain image compression. The techniques come under different categories. The study also discusses these categories.

  9. Functional Brain Imaging: A Comprehensive Survey

    CERN Document Server

    Sarraf, Saman

    2016-01-01

    Functional brain imaging allows measuring dynamic functionality in all brain regions. It is broadly used in clinical cognitive neuroscience as, well as in research. It will allow the observation of neural activities in the brain simultaneously. From the beginning when functional brain imaging was initiated by the mapping of brain functions proposed by phrenologists, many scientists were asking why we need to image brain functionality since we have already structural information. Simply, their important question was including a great answer. Functional information of the human brain would definitely complement structural information, helping to have a better understanding of what is happening in the brain. This paper, which could be useful to those who have an interest in functional brain imaging, such as engineers, will present a quick review of modalities used in functional brain imaging. We will concentrate on the most used techniques in functional imaging which are functional magnetic resonance imaging (fM...

  10. Classification of Medical Brain Images

    Institute of Scientific and Technical Information of China (English)

    Pan Haiwei(潘海为); Li Jianzhong; Zhang Wei

    2003-01-01

    Since brain tumors endanger people's living quality and even their lives, the accuracy of classification becomes more important. Conventional classifying techniques are used to deal with those datasets with characters and numbers. It is difficult, however, to apply them to datasets that include brain images and medical history (alphanumeric data), especially to guarantee the accuracy. For these datasets, this paper combines the knowledge of medical field and improves the traditional decision tree. The new classification algorithm with the direction of the medical knowledge not only adds the interaction with the doctors, but also enhances the quality of classification. The algorithm has been used on real brain CT images and a precious rule has been gained from the experiments. This paper shows that the algorithm works well for real CT data.

  11. Synthesis and evaluation of [{sup 125}I]I-TSA as a brain nicotinic acetylcholine receptor {alpha}{sub 7} subtype imaging agent

    Energy Technology Data Exchange (ETDEWEB)

    Ogawa, Mikako [Laboratory of Genome Bio-Photonics, Photon Medical Research Center, Hamamatsu Medical University, Hamamatsu 431-3192 (Japan); Tatsumi, Ryo [Pharmaceuticals Research Unit, Research and Development Division, Mitsubishi Pharma Corporation, Yokohama 227-0033 (Japan); Fujio, Masakazu [Pharmaceuticals Research Unit, Research and Development Division, Mitsubishi Pharma Corporation, Yokohama 227-0033 (Japan); Katayama, Jiro [Pharmaceuticals Research Unit, Research and Development Division, Mitsubishi Pharma Corporation, Yokohama 227-0033 (Japan); Magata, Yasuhiro [Laboratory of Genome Bio-Photonics, Photon Medical Research Center, Hamamatsu Medical University, Hamamatsu 431-3192 (Japan)]. E-mail: magata@hama-med.ac.jp

    2006-04-15

    Introduction: Some in vitro investigations have suggested that the nicotinic acetylcholine receptor (nAChR) {alpha}{sub 7} subtype is implicated in Alzheimer's disease, schizophrenia and others. Recently, we developed (R)-3'-(5-bromothiophen-2-yl)spiro[1-azabicyclo[2.2.2]octane-3,5'-[1',3'] oxazolidin]-2'-one (Br-TSA), which has a high affinity and selectivity for {alpha}{sub 7} nAChRs. Therefore we synthesized (R)-3'-(5-[{sup 125}I]iodothiophen-2-yl)spiro[1-azabicyclo[2.2.2]octane-3,5'- [1',3']oxazolidin]-2'-one ([{sup 125}I]I-TSA) and evaluated its potential for the in vivo detection of {alpha}{sub 7} nAChR in brain. Methods: In vitro binding affinity of I-TSA was measured in rat brain homogenates. Radioiodination was accomplished by a Br-I exchange reaction. Biodistribution studies were undertaken in mice by tail vein injection of [{sup 125}I]I-TSA. In vivo receptor blocking studies were carried out by treating mice with methyllycaconitine (MLA; 5 nmol/5 {mu}l, i.c.v.) or nonradioactive I-TSA (50 {mu}mol/kg, i.v.). Results: I-TSA exhibited a high affinity and selectivity for the {alpha}{sub 7} nAChR (K {sub i} for {alpha}{sub 7} nAChR=0.54 nM). Initial uptake in the brain was high (4.42 %dose/g at 5 min), and the clearance of radioactivity was relatively slow in the hippocampus ({alpha}{sub 7} nAChR-rich region) and was rather rapid in the cerebellum ({alpha}{sub 7} nAChR poor region). The hippocampus to cerebellum uptake ratio was 0.9 at 5 min postinjection, but it was increased to 1.8 at 60 min postinjection. Although the effect was not statistically significant, administration of I-TSA and MLA decreased the accumulation of radioactivity in hippocampus. Conclusion: Despite its high affinity and selectivity, [{sup 125}I]I-TSA does not appear to be a suitable tracer for in vivo {alpha}{sub 7} nAChR receptor imaging studies due to its high nonspecific binding. Further structural optimization is needed.

  12. Minireview of Stereoselective Brain Imaging

    DEFF Research Database (Denmark)

    Smith, Donald F.; Jakobsen, Steen

    2014-01-01

    Stereoselectivity is a fundamental principle in living systems. Stereoselectivity reflects the dependence of molecular processes on the spatial orientation of constituent atoms. Stereoselective processes govern many aspects of brain function and direct the course of many psychotropic drugs. Today...... animals and awake humans. The studies have demonstrated how many aspects of neurotransmission consist of crucial stereoselective events that can affect brain function in health and disease. Here, we present a brief account of those findings in hope of stimulating further interest in the vital topic......., modern imaging techniques such as SPECT and PET provide a means for studying stereoselective processes in the living brain. Chemists have prepared numerous radiolabelled stereoisomers for use in SPECT and PET in order to explore various molecular processes in the living brain of anesthetized laboratory...

  13. Liposome imaging agents in personalized medicine

    DEFF Research Database (Denmark)

    Petersen, Anncatrine Luisa; Hansen, Anders Elias; Gabizon, Alberto;

    2012-01-01

    that selectively localize in tumor tissue can transport both drugs and imaging agents, which allows for a theranostic approach with great potential in personalized medicine. Radiolabeling of liposomes have for many years been used in preclinical studies for evaluating liposome in vivo performance and has been...... start to consider how to use imaging for patient selection and treatment monitoring in connection to nanocarrier based medicines. Nanocarrier imaging agents could furthermore have interesting properties for disease diagnostics and staging. Here, we review the major advances in the development...... of radiolabeled liposomes for imaging as a tool in personalized medicine....

  14. Forthergillian Lecture. Imaging human brain function.

    Science.gov (United States)

    Frackowiak, R S

    The non-invasive brain scanning techniques introduced a quarter of a century ago have become crucial for diagnosis in clinical neurology. They have also been used to investigate brain function and have provided information about normal activity and pathogenesis. They have been used to investigate functional specialization in the brain and how specialized areas communicate to generate complex integrated functions such as speech, memory, the emotions and so on. The phenomenon of brain plasticity is poorly understood and yet clinical neurologists are aware, from everyday observations, that spontaneous recovery from brain lesions is common. An improved understanding of the mechanisms of recovery may generate new therapeutic strategies and indicate ways of modulating mechanisms that promote plastic compensation for loss of function. The main methods used to investigate these issues are positron emission tomography and magnetic resonance imaging (M.R.I.). M.R.I. is also used to map brain structure. The techniques of functional brain mapping and computational morphometrics depend on high performance scanners and a validated set of analytic statistical procedures that generate reproducible data and meaningful inferences from brain scanning data. The motor system presents a good paradigm to illustrate advances made by scanning towards an understanding of plasticity at the level of brain areas. The normal motor system is organized in a nested hierarchy. Recovery from paralysis caused by internal capsule strokes involves functional reorganization manifesting itself as changed patterns of activity in the component brain areas of the normal motor system. The pattern of plastic modification depends in part on patterns of residual or disturbed connectivity after brain injury. Therapeutic manipulations in patients with Parkinson's disease using deep brain stimulation, dopaminergic agents or fetal mesencephalic transplantation provide a means to examine mechanisms underpinning

  15. Consistent 4D Brain Extraction of Serial Brain MR Images

    OpenAIRE

    Wang, Yaping; Li, Gang; Nie, Jingxin; Yap, Pew-Thian; Guo, Lei; Shen, Dinggang

    2013-01-01

    Accurate and consistent skull stripping of serial brain MR images is of great importance in longitudinal studies that aim to detect subtle brain morphological changes. To avoid inconsistency and the potential bias introduced by independently performing skull-stripping for each time-point image, we propose an effective method that is capable of skull-stripping serial brain MR images simultaneously. Specifically, all serial images of the same subject are first affine aligned in a groupwise mann...

  16. Monkey brain cortex imaging by photoacoustic tomography

    OpenAIRE

    Yang, Xinmai; Wang, Lihong V.

    2008-01-01

    Photoacoustic tomography (PAT) is applied to image the brain cortex of a monkey through the intact scalp and skull ex vivo. The reconstructed PAT image shows the major blood vessels on the monkey brain cortex. For comparison, the brain cortex is imaged without the scalp, and then imaged again without the scalp and skull. Ultrasound attenuation through the skull is also measured at various incidence angles. This study demonstrates that PAT of the brain cortex is capable of surviving the ultras...

  17. Brain Imaging in Alzheimer Disease

    Science.gov (United States)

    Johnson, Keith A.; Fox, Nick C.; Sperling, Reisa A.; Klunk, William E.

    2012-01-01

    Imaging has played a variety of roles in the study of Alzheimer disease (AD) over the past four decades. Initially, computed tomography (CT) and then magnetic resonance imaging (MRI) were used diagnostically to rule out other causes of dementia. More recently, a variety of imaging modalities including structural and functional MRI and positron emission tomography (PET) studies of cerebral metabolism with fluoro-deoxy-d-glucose (FDG) and amyloid tracers such as Pittsburgh Compound-B (PiB) have shown characteristic changes in the brains of patients with AD, and in prodromal and even presymptomatic states that can help rule-in the AD pathophysiological process. No one imaging modality can serve all purposes as each have unique strengths and weaknesses. These modalities and their particular utilities are discussed in this article. The challenge for the future will be to combine imaging biomarkers to most efficiently facilitate diagnosis, disease staging, and, most importantly, development of effective disease-modifying therapies. PMID:22474610

  18. Neuroimaging in Traumatic Brain Imaging

    OpenAIRE

    Lee, Bruce; Newberg, Andrew

    2005-01-01

    Summary: Traumatic brain injury (TBI) is a common and potentially devastating clinical problem. Because prompt proper management of TBI sequelae can significantly alter the clinical course especially within 48 h of the injury, neuroimaging techniques have become an important part of the diagnostic work up of such patients. In the acute setting, these imaging studies can determine the presence and extent of injury and guide surgical planning and minimally invasive interventions. Neuroimaging a...

  19. Imaging brain development: the adolescent brain.

    Science.gov (United States)

    Blakemore, Sarah-Jayne

    2012-06-01

    The past 15 years have seen a rapid expansion in the number of studies using neuroimaging techniques to investigate maturational changes in the human brain. In this paper, I review MRI studies on structural changes in the developing brain, and fMRI studies on functional changes in the social brain during adolescence. Both MRI and fMRI studies point to adolescence as a period of continued neural development. In the final section, I discuss a number of areas of research that are just beginning and may be the subject of developmental neuroimaging in the next twenty years. Future studies might focus on complex questions including the development of functional connectivity; how gender and puberty influence adolescent brain development; the effects of genes, environment and culture on the adolescent brain; development of the atypical adolescent brain; and implications for policy of the study of the adolescent brain.

  20. Brain imaging, genetics and emotion.

    Science.gov (United States)

    Aleman, André; Swart, Marte; van Rijn, Sophie

    2008-09-01

    This paper reviews the published evidence on genetically driven variation in neurotransmitter function and brain circuits involved in emotion. Several studies point to a role of the serotonin transporter promoter polymorphism in amygdala activation during emotion perception. We also discuss other polymorphisms (e.g. the COMT val158met polymorphism, tryptophan hydroxylase-2 -703 G/T) and putative effects on affective processing in cortical and limbic regions. A different line of research concerns studies with genetic disorders. Although at a less fine-grained level, studies with individuals with aneuploidies of the X chromosome (Turner syndrome and Klinefelter syndrome), who display impairments in emotion processing, have resulted in new insights and hypotheses with regard to X chromosomal influences on brain systems supporting cognition and emotion. These have also implicated a key role for the amygdala. Integration of the emerging evidence, suggests that the study of polymorphisms using brain imaging can potentially elucidate biological pathways and mechanisms contributing to individual differences in brain circuits that may bias behavior and affect risk for psychiatric illness.

  1. Functional brain imaging; Funktionelle Hirnbildgebung

    Energy Technology Data Exchange (ETDEWEB)

    Gizewski, E.R. [Medizinische Universitaet Innsbruck, Universitaetsklinik fuer Neuroradiologie, Innsbruck (Austria)

    2016-02-15

    Functional magnetic resonance imaging (fMRI) is a non-invasive method that has become one of the major tools for understanding human brain function and in recent years has also been developed for clinical applications. Changes in hemodynamic signals correspond to changes in neuronal activity with good spatial and temporal resolution in fMRI. Using high-field MR systems and increasingly dedicated statistics and postprocessing, activated brain areas can be detected and superimposed on anatomical images. Currently, fMRI data are often combined in multimodal imaging, e. g. with diffusion tensor imaging (DTI) sequences. This method is helping to further understand the physiology of cognitive brain processes and is also being used in a number of clinical applications. In addition to the blood oxygenation level-dependent (BOLD) signals, this article deals with the construction of fMRI investigations, selection of paradigms and evaluation in the clinical routine. Clinically, this method is mainly used in the planning of brain surgery, analyzing the location of brain tumors in relation to eloquent brain areas and the lateralization of language processing. As the BOLD signal is dependent on the strength of the magnetic field as well as other limitations, an overview of recent developments is given. Increases of magnetic field strength (7 T), available head coils and advances in MRI analytical methods have led to constant improvement in fMRI signals and experimental design. Especially the depiction of eloquent brain regions can be done easily and quickly and has become an essential part of presurgical planning. (orig.) [German] Mittlerweile ist die funktionelle MRT (fMRT) eine Methode, die nicht mehr nur in der neurowissenschaftlichen Routine verwendet wird. Die fMRT ermoeglicht die nichtinvasive Darstellung der Hirnaktivitaet in guter raeumlicher und zeitlicher Aufloesung unter Ausnutzung der Durchblutungsaenderung aufgrund der erhoehten Nervenzellaktivitaet. Unter

  2. Development of [F-18]-Labeled Amyloid Imaging Agents for PET

    Energy Technology Data Exchange (ETDEWEB)

    Mathis, CA

    2007-05-09

    The applicant proposes to design and synthesize a series of fluorine-18-labeled radiopharmaceuticals to be used as amyloid imaging agents for positron emission tomography (PET). The investigators will conduct comprehensive iterative in vitro and in vivo studies based upon well defined acceptance criteria in order to identify lead agents suitable for human studies. The long term goals are to apply the selected radiotracers as potential diagnostic agents of Alzheimer's disease (AD), as surrogate markers of amyloid in the brain to determine the efficacy of anti-amyloid therapeutic drugs, and as tools to help address basic scientific questions regarding the progression of the neuropathology of AD, such as testing the "amyloid cascade hypothesis" which holds that amyloid accumulation is the primary cause of AD.

  3. Monkey brain cortex imaging by photoacoustic tomography.

    Science.gov (United States)

    Yang, Xinmai; Wang, Lihong V

    2008-01-01

    Photoacoustic tomography (PAT) is applied to image the brain cortex of a monkey through the intact scalp and skull ex vivo. The reconstructed PAT image shows the major blood vessels on the monkey brain cortex. For comparison, the brain cortex is imaged without the scalp, and then imaged again without the scalp and skull. Ultrasound attenuation through the skull is also measured at various incidence angles. This study demonstrates that PAT of the brain cortex is capable of surviving the ultrasound signal attenuation and distortion caused by a relatively thick skull.

  4. Brain Image Representation and Rendering: A Survey

    Directory of Open Access Journals (Sweden)

    Mudassar Raza

    2012-09-01

    Full Text Available Brain image representation and rendering processes are basically used for evaluation, development and investigation consent experimental examination and formation of brain images of a variety of modalities that includes the major brain types like MEG, EEG, PET, MRI, CT or microscopy. So, there is a need to conduct a study to review the existing work in this area. This paper provides a review of different existing techniques and methods regarding the brain image representation and rendering. Image Rendering is the method of generating an image by means of a model, through computer programs. The basic purpose of brain image representation and rendering processes is to analyze the brain images precisely in order to effectively diagnose and examine the diseases and problems. The basic objective of this study is to evaluate and discuss different techniques and approaches proposed in order to handle different brain imaging types. The paper provides a short overview of different methods, in the form of advantages and limitations, presented in the prospect of brain image representation and rendering along with their sub categories proposed by different authors.

  5. Clinical application of several tumor imaging agents

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    Neoplasms is one of the main diseases for harming health.It is difficult to prevent the neoplasms because the factors of bringing out them are complex.To raise survival rate the early diagnosis of tumors is very important.Radionuclide imaging is useful to detect recurrent or residual diseaseand to identificate benign or malignant tumor.Several tumorimaging agents as following have clinical significance indiagnosing tumors.

  6. Linking brain imaging signals to visual perception.

    Science.gov (United States)

    Welchman, Andrew E; Kourtzi, Zoe

    2013-11-01

    The rapid advances in brain imaging technology over the past 20 years are affording new insights into cortical processing hierarchies in the human brain. These new data provide a complementary front in seeking to understand the links between perceptual and physiological states. Here we review some of the challenges associated with incorporating brain imaging data into such "linking hypotheses," highlighting some of the considerations needed in brain imaging data acquisition and analysis. We discuss work that has sought to link human brain imaging signals to existing electrophysiological data and opened up new opportunities in studying the neural basis of complex perceptual judgments. We consider a range of approaches when using human functional magnetic resonance imaging to identify brain circuits whose activity changes in a similar manner to perceptual judgments and illustrate these approaches by discussing work that has studied the neural basis of 3D perception and perceptual learning. Finally, we describe approaches that have sought to understand the information content of brain imaging data using machine learning and work that has integrated multimodal data to overcome the limitations associated with individual brain imaging approaches. Together these approaches provide an important route in seeking to understand the links between physiological and psychological states.

  7. Functional brain imaging across development.

    Science.gov (United States)

    Rubia, Katya

    2013-12-01

    The developmental cognitive neuroscience literature has grown exponentially over the last decade. This paper reviews the functional magnetic resonance imaging (fMRI) literature on brain function development of typically late developing functions of cognitive and motivation control, timing and attention as well as of resting state neural networks. Evidence shows that between childhood and adulthood, concomitant with cognitive maturation, there is progressively increased functional activation in task-relevant lateral and medial frontal, striatal and parieto-temporal brain regions that mediate these higher level control functions. This is accompanied by progressively stronger functional inter-regional connectivity within task-relevant fronto-striatal and fronto-parieto-temporal networks. Negative age associations are observed in earlier developing posterior and limbic regions, suggesting a shift with age from the recruitment of "bottom-up" processing regions towards "top-down" fronto-cortical and fronto-subcortical connections, leading to a more mature, supervised cognition. The resting state fMRI literature further complements this evidence by showing progressively stronger deactivation with age in anti-correlated task-negative resting state networks, which is associated with better task performance. Furthermore, connectivity analyses during the resting state show that with development increasingly stronger long-range connections are being formed, for example, between fronto-parietal and fronto-cerebellar connections, in both task-positive networks and in task-negative default mode networks, together with progressively lesser short-range connections, suggesting progressive functional integration and segregation with age. Overall, evidence suggests that throughout development between childhood and adulthood, there is progressive refinement and integration of both task-positive fronto-cortical and fronto-subcortical activation and task-negative deactivation, leading to

  8. Effects of anesthetic agents on brain blood oxygenation level revealed with ultra-high field MRI.

    Directory of Open Access Journals (Sweden)

    Luisa Ciobanu

    Full Text Available During general anesthesia it is crucial to control systemic hemodynamics and oxygenation levels. However, anesthetic agents can affect cerebral hemodynamics and metabolism in a drug-dependent manner, while systemic hemodynamics is stable. Brain-wide monitoring of this effect remains highly challenging. Because T(2*-weighted imaging at ultra-high magnetic field strengths benefits from a dramatic increase in contrast to noise ratio, we hypothesized that it could monitor anesthesia effects on brain blood oxygenation. We scanned rat brains at 7T and 17.2T under general anesthesia using different anesthetics (isoflurane, ketamine-xylazine, medetomidine. We showed that the brain/vessels contrast in T(2*-weighted images at 17.2T varied directly according to the applied pharmacological anesthetic agent, a phenomenon that was visible, but to a much smaller extent at 7T. This variation is in agreement with the mechanism of action of these agents. These data demonstrate that preclinical ultra-high field MRI can monitor the effects of a given drug on brain blood oxygenation level in the absence of systemic blood oxygenation changes and of any neural stimulation.

  9. Return Migration After Brain Drain: An Agent Based Simulation Approach

    CERN Document Server

    Biondo, A E; Rapisarda, A

    2012-01-01

    The Brain Drain phenomenon is particularly heterogeneous and is characterized by peculiar specifications. It influences the economic fundamentals of both the country of origin and the host one in terms of human capital accumulation. Here, the brain drain is considered from a microeconomic perspective: more precisely we focus on the individual rational decision to return, referring it to the social capital owned by the worker. The presented model, restricted to the case of academic personnel, compares utility levels to justify agent's migration conduct and to simulate several scenarios with a NetLogo agent based model. In particular, we developed a simulation framework based on two fundamental individual features, i.e. risk aversion and initial expectation, which characterize the dynamics of different agents according to the random evolution of their personal social networks. Our main result is that, according to the value of risk aversion and initial expectation, the probability of return migration depends on...

  10. Brain MR imaging in dietarily treated phenylketonuria

    Energy Technology Data Exchange (ETDEWEB)

    Breysem, L. [Dept. of Radiology, University Hospitals, Leuven (Belgium); Smet, M.H. [Dept. of Radiology, University Hospitals, Leuven (Belgium); Johannik, K. [Dept. of Radiology, University Hospitals, Leuven (Belgium); Hecke, P. van [Dept. of Radiology, University Hospitals, Leuven (Belgium); Francois, B. [L. Willems Inst., Diepenbeek (Belgium); Wilms, G. [Dept. of Radiology, University Hospitals, Leuven (Belgium); Bosmans, H. [Dept. of Radiology, University Hospitals, Leuven (Belgium); Marchal, G. [Dept. of Radiology, University Hospitals, Leuven (Belgium); Jaeken, J. [Dept. of Pediatrics, University Hospitals, Leuven (Belgium); Demaerel, P. [Dept. of Radiology, University Hospitals, Leuven (Belgium)

    1994-08-01

    Magnetic resonance imaging is the most efficient imaging modality to evaluate brain gray and white matter of patients with metabolic diseases. The main purpose of our study was to investigate the relation between brain MRI abnormalities and the phenylalanine (phe) and tyrosine (tyr) blood levels in 38 phenylketonuria (PKU) patients. Increased periventricular white matter intensity on T2-weighted brain images was the only pathologic finding in 24 patients. Brain MRI abnormalities were scored (4) and correlated with the individual mean phe and phe/tyr levels during 1 year preceding MR examination and with phe tolerance. The residual activity of phenylalanine hydroxylase was defined for each patient by an oral phe tolerance. The appearance of MRI abnormalities on brain T2-weighted images correlates with a threshold mean phe level (averaged over the year preceding the examination). (orig.)

  11. Advances in Magnetic Resonance Imaging Contrast Agents for Biomarker Detection

    Science.gov (United States)

    Sinharay, Sanhita; Pagel, Mark D.

    2016-06-01

    Recent advances in magnetic resonance imaging (MRI) contrast agents have provided new capabilities for biomarker detection through molecular imaging. MRI contrast agents based on the T2 exchange mechanism have more recently expanded the armamentarium of agents for molecular imaging. Compared with T1 and T2* agents, T2 exchange agents have a slower chemical exchange rate, which improves the ability to design these MRI contrast agents with greater specificity for detecting the intended biomarker. MRI contrast agents that are detected through chemical exchange saturation transfer (CEST) have even slower chemical exchange rates. Another emerging class of MRI contrast agents uses hyperpolarized 13C to detect the agent with outstanding sensitivity. These hyperpolarized 13C agents can be used to track metabolism and monitor characteristics of the tissue microenvironment. Together, these various MRI contrast agents provide excellent opportunities to develop molecular imaging for biomarker detection.

  12. Brain imaging in type 2 diabetes.

    Science.gov (United States)

    Brundel, Manon; Kappelle, L Jaap; Biessels, Geert Jan

    2014-12-01

    Type 2 diabetes mellitus (T2DM) is associated with cognitive dysfunction and dementia. Brain imaging may provide important clues about underlying processes. This review focuses on the relationship between T2DM and brain abnormalities assessed with different imaging techniques: both structural and functional magnetic resonance imaging (MRI), including diffusion tensor imaging and magnetic resonance spectroscopy, as well as positron emission tomography and single-photon emission computed tomography. Compared to people without diabetes, people with T2DM show slightly more global brain atrophy, which increases gradually over time compared with normal aging. Moreover, vascular lesions are seen more often, particularly lacunar infarcts. The association between T2DM and white matter hyperintensities and microbleeds is less clear. T2DM has been related to diminished cerebral blood flow and cerebrovascular reactivity, particularly in more advanced disease. Diffusion tensor imaging is a promising technique with respect to subtle white matter involvement. Thus, brain imaging studies show that T2DM is associated with both degenerative and vascular brain damage, which develops slowly over the course of many years. The challenge for future studies will be to further unravel the etiology of brain damage in T2DM, and to identify subgroups of patients that will develop distinct progressive brain damage and cognitive decline.

  13. Research progress of magnetic resonance imaging contrast agents

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Magnetic resonance imaging (MRI) is a clinical diagnostic modality, which has become popular in hospitals around the world. Approximately 30% of MRI exams include the use of contrast agents. The research progress of the paramagnetic resonance imaging contrast agents was described briefly. Three important approaches in the soluble paramagnetic resonance imaging contrast agents design including nonionic, tissue-specific and macromolecular contrast agents were investigated. In addition, the problems in the research and development in future were discussed.

  14. Manganese accumulation in the brain: MR imaging

    Energy Technology Data Exchange (ETDEWEB)

    Uchino, A.; Nomiyama, K.; Takase, Y.; Nakazono, T.; Nojiri, J.; Kudo, S. [Saga Medical School, Department of Radiology, Saga (Japan); Noguchi, T. [Kyushu University, Department of Clinical Radiology, Graduate School of Medicine, Fukuoka (Japan)

    2007-09-15

    Manganese (Mn) accumulation in the brain is detected as symmetrical high signal intensity in the globus pallidi on T1-weighted MR images without an abnormal signal on T2-weighted images. In this review, we present several cases of Mn accumulation in the brain due to acquired or congenital diseases of the abdomen including hepatic cirrhosis with a portosystemic shunt, congenital biliary atresia, primary biliary cirrhosis, congenital intrahepatic portosystemic shunt without liver dysfunction, Rendu-Osler-Weber syndrome with a diffuse intrahepatic portosystemic shunt, and patent ductus venosus. Other causes of Mn accumulation in the brain are Mn overload from total parenteral nutrition and welding-related Mn intoxication. (orig.)

  15. Novel optical system for neonatal brain imaging

    Science.gov (United States)

    Chen, Yu; Zhou, Shuoming; Nioka, Shoko; Chance, Britton; Anday, Endla; Ravishankar, Sudha; Delivoria-Papadopoulos, Maria

    1999-03-01

    A highly portable, fast, safe and affordable imaging system that provides interpretable images of brain function in full- and pre-term neonates within a few seconds has been applied to neonates with normal and pathological states. We have used a uniquely sensitive optical tomography system, termed phased array, which has revealed significant functional responses, particularly to parietal stimulation in neonate brain. This system can indicate the blood concentration and oxygenation change during the parietal brain activation in full- and pre-term neonates. The preliminary clinical results, especially a longitudinal study of a cardiac arrest neonate, suggest a variety of future applications.

  16. MRI Brain Image Segmentation based on Thresholding

    Directory of Open Access Journals (Sweden)

    G. Evelin Sujji, Y.V.S. Lakshmi, G. Wiselin Jiji

    2013-03-01

    Full Text Available Medical Image processing is one of the mostchallenging topics in research field. The mainobjective of image segmentation is to extract variousfeatures of the image that are used foranalysing,interpretation and understanding of images.Medical Resonance Image plays a major role inMedical diagnostics. Image processing in MRI ofbrain is highlyessential due to accurate detection ofthe type of brain abnormality which can reduce thechance of fatal result. This paper outlines anefficient image segmentation technique that candistinguish the pathological tissues such asedemaandtumourfrom thenormal tissues such as WhiteMatter(WM,GreyMatter(GM, andCerebrospinal Fluid(CSF. Thresholding is simplerand most commonly used techniques in imagesegmentation. This technique can be used to detectthe contour of thetumourin brain.

  17. Magnetic resonance imaging of brain death

    Energy Technology Data Exchange (ETDEWEB)

    Lee, D.H.; Nathanson, J.A.; Fox, A.J.; Pelz, D.M.; Lownie, S.P.

    1995-06-01

    In order to demonstrate the magnetic resonance imaging (MRI) appearance of the brain in patients with clinical brain death, high-field MRI was performed on 5 patients using conventional T1-weighted and T2-weighted imaging. The study showed MRI exhibited similar features for all of the patients, features which were not found in MRI of comatose patients who were not clinically brain dead. It was stated that up to now the most important limitation in MRI of patients with suspected brain death has been the extreme difficulty of moving them out of the intensive care setting. If this problem can be overcome, and it appears possible with with the advent of MRI-compatible ventilators and noninvasive monitoring, MRI could become an excellent alternative for confirming clinical diagnosis of brain death for such patients. 15 refs., 3 figs.

  18. CT scan of the brain (image)

    Science.gov (United States)

    ... CAT scan (computed tomography) is a much more sensitive imaging technique than x-ray, allowing high definition not only of the bony structures, but of the soft tissues. Clear images of organs such as the brain, muscles, joint structures, veins ...

  19. Brain Morphometry Using Anatomical Magnetic Resonance Imaging

    Science.gov (United States)

    Bansal, Ravi; Gerber, Andrew J.; Peterson, Bradley S.

    2008-01-01

    The efficacy of anatomical magnetic resonance imaging (MRI) in studying the morphological features of various regions of the brain is described, also providing the steps used in the processing and studying of the images. The ability to correlate these features with several clinical and psychological measures can help in using anatomical MRI to…

  20. Detection of brain tumors using fluorescence diffuse optical tomography and nanoparticles as contrast agents

    Science.gov (United States)

    Fortin, Pierre-Yves; Genevois, Coralie; Koenig, Anne; Heinrich, Emilie; Texier, Isabelle; Couillaud, Franck

    2012-12-01

    Near-infrared fluorescence-enhanced diffuse optical tomography (fDOT) is used to localize tumors in mice using fluorescent nanoparticles as a blood pool contrast agent. The infrared dye DiR is loaded in the lipid core of nontargeted nanoparticles (DiR-lipidots) and injected systemically via the tail vein in mice bearing U87 tumors. Distribution and time-course of DiR-lipidots are followed using in vivo fluorescence reflectance imaging and reveal enhanced fluorescent signal within the subcutaneous tumors up to seven days due to the enhanced permeability and retention effect. Tumor growth into the brain is followed using bioluminescent imaging, and tumor localization is further determined by magnetic resonance imaging. The fDOT provides three-dimensional fluorescent maps that allow for consistent localization for both subcutaneous and brain tumors.

  1. Advantages in functional imaging of the brain

    Directory of Open Access Journals (Sweden)

    Walter eMier

    2015-05-01

    Full Text Available As neuronal pathologies cause only minor morphological alterations, molecular imaging techniques are a prerequisite for the study of diseases of the brain. The development of molecular probes that specifically bind biochemical markers and the advances of instrumentation have revolutionized the possibilities to gain insight into the human brain organization and beyond this visualize structure-function and brain-behavior relationships. The review describes the development and current applications of functional brain imaging techniques with a focus on applications in psychiatry. A historical overview of the development of functional imaging is followed by the portrayal of the principles and applications of positron emission tomography (PET and functional magnetic resonance imaging (fMRI, two key molecular imaging techniques that have revolutionized the ability to image molecular processes in the brain. In the juxtaposition of PET and fMRI in hybrid PET/MRI scanners enhances the significance of both modalities for research in neurology and psychiatry and might pave the way for a new area of personalized medicine.

  2. Classification and basic properties of contrast agents for magnetic resonance imaging.

    Science.gov (United States)

    Geraldes, Carlos F G C; Laurent, Sophie

    2009-01-01

    A comprehensive classification of contrast agents currently used or under development for magnetic resonance imaging (MRI) is presented. Agents based on small chelates, macromolecular systems, iron oxides and other nanosystems, as well as responsive, chemical exchange saturation transfer (CEST) and hyperpolarization agents are covered in order to discuss the various possibilities of using MRI as a molecular imaging technique. The classification includes composition, magnetic properties, biodistribution and imaging applications. Chemical compositions of various classes of MRI contrast agents are tabulated, and their magnetic status including diamagnetic, paramagnetic and superparamagnetic are outlined. Classification according to biodistribution covers all types of MRI contrast agents including, among others, extracellular, blood pool, polymeric, particulate, responsive, oral, and organ specific (hepatobiliary, RES, lymph nodes, bone marrow and brain). Various targeting strategies of molecular, macromolecular and particulate carriers are also illustrated.

  3. Development of Tc-99m Imaging Agents for Abeta Plaques

    Energy Technology Data Exchange (ETDEWEB)

    Zhi-Ping, Zhuang; Mei-Ping Kung; Catherihne Hou; Hank F. Kung

    2008-09-26

    Development of SPECT imaging agents based on Tc-99m targeting Aβ plaques is useful for diagnosis of Alzheimer’s disease (AD). A stilbene derivative, [11C]SB-13, showing promise in detecting senile plaques present in AD patients has been reported previously1,2. Based on the 4’-amino-stilbene core structure we have added substituted groups through which a chelating group, N2S2, was conjugated. We report herein a series of Tc-99m labeled stilbene derivative conjugated with a TcO[N2S2] core. The syntheses of stilbenes containing a N2S2 chelating ligand are achieved by a scheme shown. Lipophilic 99mTc stilbene complexes were successfully prepared and purified through HPLC. Preliminary results of in vitro labeling of brain sections from transgenic mice showed very promising plaque labeling. These 99mTc stilbene derivatives are warranted for further evaluations as potential imaging agents targeting amyloid plaques.

  4. Nootropic agents stimulate neurogenesis. Brain Cells, Inc.: WO2007104035.

    Science.gov (United States)

    Taupin, Philippe

    2009-05-01

    The application is in the field of adult neurogenesis, neural stem cells and cellular therapy. It aims to characterize the activity of nootropic agents on adult neurogenesis in vitro. Nootropic agents are substances improving cognitive and mental abilities. AMPA (alpha-amino-3-hydroxyl-5-methyl-4-isoxazole-propionate) and nootropic agents were assessed for the potential to differentiate human neural progenitor and stem cells into neuronal cells in vitro. They were also tested for their behavioural activity on the novel object recognition task. AMPA, piracetam, FK-960 and SGS-111 induce and stimulate neuronal differentiation of human-derived neural progenitor and stem cells. SGS-111 increases the number of visits to the novel object. The neurogenic activity of piracetam and SGS-111 is mediated through AMPA receptor. The neurogenic activity of SGS-111 may contribute and play a role in its nootropic activity. These results suggest that nootropic agents may elicit some of their effects through their neurogenic activity. The application claims the use of nootropic agents for their neurogenic activity and for the treatment of neurological diseases, disorders and injuries, by stimulating or increasing the generation of neuronal cells in the adult brain.

  5. Brain imaging, genetics and emotion

    NARCIS (Netherlands)

    Aleman, Andre; Swart, Marte; van Rijn, Sophie

    2008-01-01

    This paper reviews the published evidence on genetically driven variation in neurotransmitter function and brain circuits involved in emotion. Several studies point to a role of the serotonin transporter promoter polymorphism in amygdala activation during emotion perception. We also discuss other po

  6. Imaging of Traumatic Brain Injury

    NARCIS (Netherlands)

    Zagorchev, L.; McAllister, T.

    2011-01-01

    Traumatic brain injury (TBI) represents an enormous public health challenge and is often associated with life long neurobehavioral sequelae in survivors. Several factors including higher percentages of individuals surviving TBI, as well as increasing concern about potential long term sequelae of ev

  7. Proton MRS imaging in pediatric brain tumors

    Energy Technology Data Exchange (ETDEWEB)

    Zarifi, Maria [Aghia Sophia Children' s Hospital, Department of Radiology, Athens (Greece); Tzika, A.A. [Harvard Medical School, Department of Surgery, Massachusetts General Hospital, Boston, MA (United States); Shriners Burn Hospital, Boston, MA (United States)

    2016-06-15

    Magnetic resonance (MR) techniques offer a noninvasive, non-irradiating yet sensitive approach to diagnosing and monitoring pediatric brain tumors. Proton MR spectroscopy (MRS), as an adjunct to MRI, is being more widely applied to monitor the metabolic aspects of brain cancer. In vivo MRS biomarkers represent a promising advance and may influence treatment choice at both initial diagnosis and follow-up, given the inherent difficulties of sequential biopsies to monitor therapeutic response. When combined with anatomical or other types of imaging, MRS provides unique information regarding biochemistry in inoperable brain tumors and can complement neuropathological data, guide biopsies and enhance insight into therapeutic options. The combination of noninvasively acquired prognostic information and the high-resolution anatomical imaging provided by conventional MRI is expected to surpass molecular analysis and DNA microarray gene profiling, both of which, although promising, depend on invasive biopsy. This review focuses on recent data in the field of MRS in children with brain tumors. (orig.)

  8. IMAGING THE BRAIN AS SCHIZOPHRENIA DEVELOPS: DYNAMIC & GENETIC BRAIN MAPS.

    Science.gov (United States)

    Thompson, Paul; Rapoport, Judith L; Cannon, Tyrone D; Toga, Arthur W

    2002-01-01

    Schizophrenia is a chronic, debilitating psychiatric disorder that affects 0.2-2% of the population worldwide. Often striking without warning in the late teens or early twenties, its symptoms include auditory and visual hallucinations, psychotic outbreaks, bizarre or disordered thinking, depression and social withdrawal. To combat the disease, new antipsychotic drugs are emerging; these atypical neuroleptics target dopamine and serotonin pathways in the brain, offering increased therapeutic efficacy with fewer side effects. Despite their moderate success in controlling some patients' symptoms, little is known about the causes of schizophrenia, and what triggers the disease. Its peculiar age of onset raises key questions: What physical changes occur in the brain as a patient develops schizophrenia? Do these deficits spread in the brain, and can they be opposed? How do they relate to psychotic symptoms? As risk for the disease is genetically transmitted, do a patient's relatives exhibit similar brain changes? Recent advances in brain imaging and genetics provide exciting insight on these questions. Neuroimaging can now chart the emergence and progression of deficits in the brain, providing an exceptionally sharp scalpel to dissect the effects of genetic risk, environmental triggers, and susceptibility genes. Visualizing the dynamics of the disease, these techniques also offer new strategies to evaluate drugs that combat the unrelenting symptoms of schizophrenia.

  9. Brain 'imaging' in the Renaissance.

    Science.gov (United States)

    Paluzzi, Alessandro; Belli, Antonio; Bain, Peter; Viva, Laura

    2007-12-01

    During the Renaissance, a period of 'rebirth' for humanities and science, new knowledge and speculation began to emerge about the function of the human body, replacing ancient religious and philosophical dogma. The brain must have been a fascinating mystery to a Renaissance artist, but some speculation existed at that time on the function of its parts. Here we show how revived interest in anatomy and life sciences may have influenced the figurative work of Italian and Flemish masters, such as Rafael, Michelangelo and David. We present a historical perspective on the artists and the period in which they lived, their fascination for human anatomy and its symbolic use in their art. Prior to the 16th century, knowledge of the brain was limited and influenced in a dogmatic way by the teachings of Galen(1) who, as we now know, conducted his anatomical studies not on humans but on animals.(2) Nemesus, Bishop of Emesa, in around the year 400 was one of the first to attribute mental faculties to the brain, specifically to the ventricles. He identified two anterior (lateral) ventricles, to which he assigned perception, a middle ventricle responsible for cognition and a posterior ventricle for memory.(2,3) After a long period of stasis in the Middle Ages, Renaissance scholars realized the importance of making direct observations on dissected cadavers. Between 1504 and 1507, Leonardo da Vinci conducted experiments to reveal the anatomy of the ventricular system in the brain. He injected hot wax through a tube thrust into the ventricular cavities of an ox and then scraped the overlying brain off, thus obtaining, in a simple but ingenious way, an accurate cast of the ventricles.(2,4) Leonardo shared the belief promoted by scholarly Christians that the ventricles were the abode of rational soul. We have several examples of hidden symbolism in Renaissance paintings, but the influence of phrenology and this rudimentary knowledge of neuroanatomy on artists of that period is under

  10. Simultaneous imaging of MR angiographic image and brain surface image using steady-state free precession

    Energy Technology Data Exchange (ETDEWEB)

    Takane, Atsushi; Tsuda, Munetaka (Hitachi Ltd., Katsuta, Ibaraki (Japan)); Koizumi, Hideaki; Koyama, Susumu; Yoshida, Takeyuki

    1993-09-01

    Synthesis of a brain surface image and an angiographic image representing brain surface vasculatures can be useful for pre-operational contemplation of brain surgery. Both brain surface images and brain surface vasculature images were successfully acquired simultaneously utilizing both FID signals and time-reversed FID signals created under steady-state free precession (SSFP). This simultaneous imaging method has several advantages. No positional discrepancies between both images and prolongation of scan time are anticipated because of concurrent acquisition of the two kinds of image data. Superimposition and stereo-display of both images enable understanding of their spatial relationship, and therefore afford a useful means for pre-operational simulation of brain surgery. (author).

  11. Magnetic Resonance Imaging Contrast Agents: A Review of Literature

    Directory of Open Access Journals (Sweden)

    Zahra Sahraei

    2015-10-01

    Full Text Available  Magnetic Resonance Imaging (MRI contrast agents most commonly agents used in diagnosing different diseases. Several agents have been ever introduced with different peculiar characteristics. They vary in potency, adverse reaction and other specification, so it is important to select the proper agent in different situations. We conducted a systematic literature search in MEDLINE/PUBMED, Web of Science (ISI, Scopus,Google Scholar by using keywords "gadolinium" and "MRI contrast Medias", "Gadofosvest", "Gadobenate" and "Gadoxetate". The most frequent contrast media agents made based on gadolinium (Gd. These are divided into two categories based on the structure of their chelating parts, linear agents and macrocyclic agents. All characteristics of contrast media factors, including efficiency, kinetic properties, stability, side effects and the rate of resolution are directly related to the structure of chelating part of that formulation.In vitro data has shown that the macrocyclic compounds are the most stable Gd-CA as they do not bind to serum proteins, they all possess similar and relatively low relaxivity and the prevalence of Nephrogenic Systemic Fibrosis (NSF has decreased by increasing the use of macrocyclic agents in recent years. No cases of NSF have been recorded after the administration of any of the high-relaxivity protein interacting agents, the vascular imaging agent gadofosveset trisodium (Ablavar, the hepatic imaging agent gadoxetate meglumine (Eovist, and the multipurpose agent gadobenate dimeglumine (MultiHance. In pregnancy and lactating women, stable macrocyclic agent is recommended.

  12. Image reconstruction for brain CT slices

    Institute of Scientific and Technical Information of China (English)

    吴建明; 施鹏飞

    2004-01-01

    Different modalities in biomedical images, like CT, MRI and PET scanners, provide detailed cross-sectional views of human anatomy. This paper introduces three-dimensional brain reconstruction based on CT slices. It contains filtering, fuzzy segmentation, matching method of contours, cell array structure and image animation. Experimental results have shown its validity. The innovation is matching method of contours and fuzzy segmentation algorithm of CT slices.

  13. Formulations for Intranasal Delivery of Pharmacological Agents to Combat Brain Disease: A New Opportunity to Tackle GBM?

    Directory of Open Access Journals (Sweden)

    Stefaan W. van Gool

    2013-08-01

    Full Text Available Despite recent advances in tumor imaging and chemoradiotherapy, the median overall survival of patients diagnosed with glioblastoma multiforme does not exceed 15 months. Infiltration of glioma cells into the brain parenchyma, and the blood-brain barrier are important hurdles to further increase the efficacy of classic therapeutic tools. Local administration methods of therapeutic agents, such as convection enhanced delivery and intracerebral injections, are often associated with adverse events. The intranasal pathway has been proposed as a non-invasive alternative route to deliver therapeutics to the brain. This route will bypass the blood-brain barrier and limit systemic side effects. Upon presentation at the nasal cavity, pharmacological agents reach the brain via the olfactory and trigeminal nerves. Recently, formulations have been developed to further enhance this nose-to-brain transport, mainly with the use of nanoparticles. In this review, the focus will be on formulations of pharmacological agents, which increase the nasal permeation of hydrophilic agents to the brain, improve delivery at a constant and slow release rate, protect therapeutics from degradation along the pathway, increase mucoadhesion, and facilitate overall nasal transport. A mounting body of evidence is accumulating that the underexplored intranasal delivery route might represent a major breakthrough to combat glioblastoma.

  14. Imaging biomarkers in primary brain tumours

    Energy Technology Data Exchange (ETDEWEB)

    Lopci, Egesta; Chiti, Arturo [Humanitas Clinical and Research Center, Nuclear Medicine Department, Rozzano, MI (Italy); Franzese, Ciro; Navarria, Pierina; Scorsetti, Marta [Humanitas Clinical and Research Center, Radiosurgery and Radiotherapy, Rozzano, MI (Italy); Grimaldi, Marco [Humanitas Clinical and Research Center, Radiology, Rozzano, MI (Italy); Zucali, Paolo Andrea; Simonelli, Matteo [Humanitas Clinical and Research Center, Medical Oncology, Rozzano, MI (Italy); Bello, Lorenzo [Humanitas Clinical and Research Center, Neurosurgery, Rozzano, MI (Italy)

    2015-04-01

    We are getting used to referring to instrumentally detectable biological features in medical language as ''imaging biomarkers''. These two terms combined reflect the evolution of medical imaging during recent decades, and conceptually comprise the principle of noninvasive detection of internal processes that can become targets for supplementary therapeutic strategies. These targets in oncology include those biological pathways that are associated with several tumour features including independence from growth and growth-inhibitory signals, avoidance of apoptosis and immune system control, unlimited potential for replication, self-sufficiency in vascular supply and neoangiogenesis, acquired tissue invasiveness and metastatic diffusion. Concerning brain tumours, there have been major improvements in neurosurgical techniques and radiotherapy planning, and developments of novel target drugs, thus increasing the need for reproducible, noninvasive, quantitative imaging biomarkers. However, in this context, conventional radiological criteria may be inappropriate to determine the best therapeutic option and subsequently to assess response to therapy. Integration of molecular imaging for the evaluation of brain tumours has for this reason become necessary, and an important role in this setting is played by imaging biomarkers in PET and MRI. In the current review, we describe most relevant techniques and biomarkers used for imaging primary brain tumours in clinical practice, and discuss potential future developments from the experimental context. (orig.)

  15. Brain Imaging Studies of Developmental Stuttering.

    Science.gov (United States)

    Ingham, Roger J.

    2001-01-01

    A review of research on brain imaging of developmental stuttering concludes that findings increasingly point to a failure of normal temporal lobe activation during speech that may either contribute to (or is the result of) a breakdown in the sequencing of processing among premotor regions implicated in phonologic planning. (Contains references.)…

  16. History and evolution of brain tumor imaging: insights through radiology.

    Science.gov (United States)

    Castillo, Mauricio

    2014-11-01

    This review recounts the history of brain tumor diagnosis from antiquity to the present and, indirectly, the history of neuroradiology. Imaging of the brain has from the beginning held an enormous interest because of the inherent difficulty of this endeavor due to the presence of the skull. Because of this, most techniques when newly developed have always been used in neuroradiology and, although some have proved to be inappropriate for this purpose, many were easily incorporated into the specialty. The first major advance in modern neuroimaging was contrast agent-enhanced computed tomography, which permitted accurate anatomic localization of brain tumors and, by virtue of contrast enhancement, malignant ones. The most important advances in neuroimaging occurred with the development of magnetic resonance imaging and diffusion-weighted sequences that allowed an indirect estimation of tumor cellularity; this was further refined by the development of perfusion and permeability mapping. From its beginnings with indirect and purely anatomic imaging techniques, neuroradiology now uses a combination of anatomic and physiologic techniques that will play a critical role in biologic tumor imaging and radiologic genomics.

  17. Brain imaging of affective disorders and schizophrenia.

    Science.gov (United States)

    Kishimoto, H; Yamada, K; Iseki, E; Kosaka, K; Okoshi, T

    1998-12-01

    We review recent findings in human brain imaging, for example, which brain areas are used during perception of colors, moving objects, human faces, facial expressions, sadness and happiness etc. One study used fluorine-18-labeled deoxyglucose positron emission tomography (PET) in patients with unipolar depression and bipolar depression, and found hypometabolism in the left anterolateral prefrontal cortex. Another study reported increased regional cerebral blood flow in the amygdala in familial pure depressive disease. Using 11C-glucose PET, we reported that the glutamic acid pool was reduced in cortical areas of the brain in patients with major depression. We also found that the thalamic and cingulate areas were hyperactive in drug-naive (never medicated) acute schizophrenics, while the associative frontal, parietal, temporal gyri were hypoactive in drug-naive chronic schizophrenics. Brain biochemical disturbances of schizophrenic patients involved glutamic acid, N-acetyl aspartic acid, phosphatidylcholine and sphingomyelin which are important chemical substances in the working brain. The areas of the thalamus and the cingulate which become hyperactive in acute schizophrenic patients are important brain areas for perception and communication. The association areas of the cortex which become disturbed in chronic schizophrenia are essential brain areas in human creativity (language, concepts, formation of cultures and societies) and exist only in human beings.

  18. Analysis of Dynamic Brain Imaging Data

    CERN Document Server

    Mitra, P

    1998-01-01

    Modern imaging techniques for probing brain function, including functional Magnetic Resonance Imaging, intrinsic and extrinsic contrast optical imaging, and magnetoencephalography, generate large data sets with complex content. In this paper we develop appropriate techniques of analysis and visualization of such imaging data, in order to separate the signal from the noise, as well as to characterize the signal. The techniques developed fall into the general category of multivariate time series analysis, and in particular we extensively use the multitaper framework of spectral analysis. We develop specific protocols for the analysis of fMRI, optical imaging and MEG data, and illustrate the techniques by applications to real data sets generated by these imaging modalities. In general, the analysis protocols involve two distinct stages: `noise' characterization and suppression, and `signal' characterization and visualization. An important general conclusion of our study is the utility of a frequency-based repres...

  19. Imaging Study Confirms Brain Differences in People with ADHD

    Science.gov (United States)

    ... Imaging Study Confirms Brain Differences in People With ADHD Attention-deficit/hyperactivity should be considered a brain ... Researchers who pinpointed brain differences in people with attention-deficit/hyperactivity disorder (ADHD) say their findings show the condition should ...

  20. Intelligent Design of Nano-Scale Molecular Imaging Agents

    Directory of Open Access Journals (Sweden)

    Takeaki Ozawa

    2012-12-01

    Full Text Available Visual representation and quantification of biological processes at the cellular and subcellular levels within living subjects are gaining great interest in life science to address frontier issues in pathology and physiology. As intact living subjects do not emit any optical signature, visual representation usually exploits nano-scale imaging agents as the source of image contrast. Many imaging agents have been developed for this purpose, some of which exert nonspecific, passive, and physical interaction with a target. Current research interest in molecular imaging has mainly shifted to fabrication of smartly integrated, specific, and versatile agents that emit fluorescence or luminescence as an optical readout. These agents include luminescent quantum dots (QDs, biofunctional antibodies, and multifunctional nanoparticles. Furthermore, genetically encoded nano-imaging agents embedding fluorescent proteins or luciferases are now gaining popularity. These agents are generated by integrative design of the components, such as luciferase, flexible linker, and receptor to exert a specific on–off switching in the complex context of living subjects. In the present review, we provide an overview of the basic concepts, smart design, and practical contribution of recent nano-scale imaging agents, especially with respect to genetically encoded imaging agents.

  1. Three-dimensional reconstruction of functional brain images

    Energy Technology Data Exchange (ETDEWEB)

    Inoue, Masato; Shoji, Kazuhiko; Kojima, Hisayoshi; Hirano, Shigeru; Naito, Yasushi; Honjo, Iwao [Kyoto Univ. (Japan)

    1999-08-01

    We consider PET (positron emission tomography) measurement with SPM (Statistical Parametric Mapping) analysis to be one of the most useful methods to identify activated areas of the brain involved in language processing. SPM is an effective analytical method that detects markedly activated areas over the whole brain. However, with the conventional presentations of these functional brain images, such as horizontal slices, three directional projection, or brain surface coloring, makes understanding and interpreting the positional relationships among various brain areas difficult. Therefore, we developed three-dimensionally reconstructed images from these functional brain images to improve the interpretation. The subjects were 12 normal volunteers. The following three types of images were constructed: routine images by SPM, three-dimensional static images, and three-dimensional dynamic images, after PET images were analyzed by SPM during daily dialog listening. The creation of images of both the three-dimensional static and dynamic types employed the volume rendering method by VTK (The Visualization Toolkit). Since the functional brain images did not include original brain images, we synthesized SPM and MRI brain images by self-made C++ programs. The three-dimensional dynamic images were made by sequencing static images with available software. Images of both the three-dimensional static and dynamic types were processed by a personal computer system. Our newly created images showed clearer positional relationships among activated brain areas compared to the conventional method. To date, functional brain images have been employed in fields such as neurology or neurosurgery, however, these images may be useful even in the field of otorhinolaryngology, to assess hearing and speech. Exact three-dimensional images based on functional brain images are important for exact and intuitive interpretation, and may lead to new developments in brain science. Currently, the surface

  2. Fast optical imaging of human brain function

    Directory of Open Access Journals (Sweden)

    Gabriele Gratton

    2010-06-01

    Full Text Available Great advancements in brain imaging during the last few decades have opened a large number of new possibilities for neuroscientists. The most dominant methodologies (electrophysiological and magnetic resonance-based methods emphasize temporal and spatial information, respectively. However, theorizing about brain function has recently emphasized the importance of rapid (within 100 ms or so interactions between different elements of complex neuronal networks. Fast optical imaging, and in particular the event-related optical signal (EROS, a technology that has emerged over the last 15 years may provide descriptions of localized (to sub-cm level brain activity with a temporal resolution of less than 100 ms. The main limitations of EROS are its limited penetration, which allows us to image cortical structures not deeper than 3 cm from the surface of the head, and its low signal-to-noise ratio. Advantages include the fact that EROS is compatible with most other imaging methods, including electrophysiological, magnetic resonance, and trans-cranial magnetic stimulation techniques, with which can be recorded concurrently. In this paper we present a summary of the research that has been conducted so far on fast optical imaging, including evidence for the possibility of recording neuronal signals with this method, the properties of the signals, and various examples of applications to the study of human cognitive neuroscience. Extant issues, controversies, and possible future developments are also discussed.

  3. Thresholding magnetic resonance images of human brain

    Institute of Scientific and Technical Information of China (English)

    Qing-mao HU; Wieslaw L NOWINSKI

    2005-01-01

    In this paper, methods are proposed and validated to determine low and high thresholds to segment out gray matter and white matter for MR images of different pulse sequences of human brain. First, a two-dimensional reference image is determined to represent the intensity characteristics of the original three-dimensional data. Then a region of interest of the reference image is determined where brain tissues are present. The non-supervised fuzzy c-means clustering is employed to determine: the threshold for obtaining head mask, the low threshold for T2-weighted and PD-weighted images, and the high threshold for T1-weighted, SPGR and FLAIR images. Supervised range-constrained thresholding is employed to determine the low threshold for T1-weighted, SPGR and FLAIR images. Thresholding based on pairs of boundary pixels is proposed to determine the high threshold for T2- and PD-weighted images. Quantification against public data sets with various noise and inhomogeneity levels shows that the proposed methods can yield segmentation robust to noise and intensity inhomogeneity. Qualitatively the proposed methods work well with real clinical data.

  4. Optical Coherence Tomography for Brain Imaging

    Science.gov (United States)

    Liu, Gangjun; Chen, Zhongping

    Recently, there has been growing interest in using OCT for brain imaging. A feasibility study of OCT for guiding deep brain probes has found that OCT can differentiate the white matter and gray matter because the white matter tends to have a higher peak reflectivity and steeper attenuation rate compared to gray matter. In vivo 3D visualization of the layered organization of a rat olfactory bulb with OCT has been demonstrated. OCT has been used for single myelin fiber imaging in living rodents without labeling. The refractive index in the rat somatosensory cortex has also been measured with OCT. In addition, functional extension of OCT, such as Doppler-OCT (D-OCT), polarization sensitive-OCT (PS-OCT), and phase-resolved-OCT (PR-OCT), can image and quantify physiological parameters in addition to the morphological structure image. Based on the scattering changes during neural activity, OCT has been used to measure the functional activation in neuronal tissues. PS-OCT, which combines polarization sensitive detection with OCT to determine tissue birefringence, has been used for the localization of nerve fiber bundles and the mapping of micrometer-scale fiber pathways in the brain. D-OCT, also named optical Doppler tomography (ODT), combines the Doppler principle with OCT to obtain high resolution tomographic images of moving constituents in highly scattering biological tissues. D-OCT has been successfully used to image cortical blood flow and map the blood vessel network for brain research. In this chapter, the principle and technology of OCT and D-OCT are reviewed and examples of potential applications are described.

  5. Visceral Afferent Pathways and Functional Brain Imaging

    Directory of Open Access Journals (Sweden)

    Stuart W.G. Derbyshire

    2003-01-01

    Full Text Available The application of functional imaging to study painful sensations has generated considerable interest regarding insight into brain dysfunction that may be responsible for functional pain such as that suffered in patients with irritable bowel syndrome (IBS. This review provides a brief introduction to the development of brain science as it relates to pain processing and a snapshot of recent functional imaging results with somatic and visceral pain. Particular emphasis is placed on current hypotheses regarding dysfunction of the brain-gut axis in IBS patients. There are clear and interpretable differences in brain activation following somatic as compared with visceral noxious sensation. Noxious visceral distension, particularly of the lower gastrointestinal tract, activates regions associated with unpleasant affect and autonomic responses. Noxious somatic sensation, in contrast, activates regions associated with cognition and skeletomotor responses. Differences between IBS patients and control subjects, however, were far less clear and interpretable. While this is in part due to the newness of this field, it also reflects weaknesses inherent within the current understanding of IBS. Future use of functional imaging to examine IBS and other functional disorders will be more likely to succeed by describing clear theoretical and clinical endpoints.

  6. Electromagnetic imaging of dynamic brain activity

    Energy Technology Data Exchange (ETDEWEB)

    Mosher, J.; Leahy, R. [University of Southern California, Los Angeles, CA (United States). Dept. of Electrical Engineering; Lewis, P.; Lewine, J.; George, J. [Los Alamos National Lab., NM (United States); Singh, M. [University of Southern California, Los Angeles, CA (United States). Dept. of Radiology

    1991-12-31

    Neural activity in the brain produces weak dynamic electromagnetic fields that can be measured by an array of sensors. Using a spatio-temporal modeling framework, we have developed a new approach to localization of multiple neural sources. This approach is based on the MUSIC algorithm originally developed for estimating the direction of arrival of signals impinging on a sensor array. We present applications of this technique to magnetic field measurements of a phantom and of a human evoked somatosensory response. The results of the somatosensory localization are mapped onto the brain anatomy obtained from magnetic resonance images.

  7. MR imaging of the fetal brain

    Energy Technology Data Exchange (ETDEWEB)

    Glenn, Orit A. [University of California, San Francisco, Department of Radiology, Neuroradiology Section, San Francisco, CA (United States)

    2010-01-15

    Fetal MRI is clinically performed to evaluate the brain in cases where an abnormality is detected by prenatal sonography. These most commonly include ventriculomegaly, abnormalities of the corpus callosum, and abnormalities of the posterior fossa. Fetal MRI is also increasingly performed to evaluate fetuses who have normal brain findings on prenatal sonogram but who are at increased risk for neurodevelopmental abnormalities, such as complicated monochorionic twin pregnancies. This paper will briefly discuss the common clinical conditions imaged by fetal MRI as well as recent advances in fetal MRI research. (orig.)

  8. MMP-2/9-Specific Activatable Lifetime Imaging Agent

    Directory of Open Access Journals (Sweden)

    Marcus T.M. Rood

    2015-05-01

    Full Text Available Optical (molecular imaging can benefit from a combination of the high signal-to-background ratio of activatable fluorescence imaging with the high specificity of luminescence lifetime imaging. To allow for this combination, both imaging techniques were integrated in a single imaging agent, a so-called activatable lifetime imaging agent. Important in the design of this imaging agent is the use of two luminophores that are tethered by a specific peptide with a hairpin-motive that ensured close proximity of the two while also having a specific amino acid sequence available for enzymatic cleavage by tumor-related MMP-2/9. Ir(ppy3 and Cy5 were used because in close proximity the emission intensities of both luminophores were quenched and the influence of Cy5 shortens the Ir(ppy3 luminescence lifetime from 98 ns to 30 ns. Upon cleavage in vitro, both effects are undone, yielding an increase in Ir(ppy3 and Cy5 luminescence and a restoration of Ir(ppy3 luminescence lifetime to 94 ns. As a reference for the luminescence activation, a similar imaging agent with the more common Cy3-Cy5 fluorophore pair was used. Our findings underline that the combination of enzymatic signal activation with lifetime imaging is possible and that it provides a promising method in the design of future disease specific imaging agents.

  9. Advances in brain imaging of neuropathic pain

    Institute of Scientific and Technical Information of China (English)

    CHEN Fu-yong; TAO Wei; LI Yong-jie

    2008-01-01

    Objective To review the literature on the use of brain imaging,including functional magnetic resonance imaging(fMRI), positron emission tomography(PET),magnetic resonance spectroscopy(MRS)and voxel-based morphometry(VBM)in investigation of the activity in diverse brain regions that creates and modulates chronic neuropathic pain. Data sources English literatures from January 1,2000 to July 31,2007 that examined human brain activity in chronic neuropathic pain were accessed through MEDLINE/CD ROM,using PET,fMRI,VBM,MRS and receptor binding. Study selection Published articles about the application of fMRI,PET,VBM,MRS and chronic neuropathic pain were selected. Data extraction Data were mainly extracted from 40 representative articles as the research basis. Results The PET studies suggested that spontaneous neuropathic pain is associated with changes in thalamic activity. Both PET and fMRI have been used to investigate the substrate of allodynia.The VBM demonstrated that brain structural changes are involved in chronic neuropathic pain,which is not seen in a matched control group.However,the results obtained had a large variety,which may be due to different pain etiology,pain distribution,lesion tomography,symptoms and stimulation procedures. Conclusions Application of the techniques of brain imaging plays a very important role in the study of structural and functional reorganization In patients with neuropathic pain.However,a unique"pain matrix" has not been defined.Future studies should be conducted using a prospective longitudinal research design,which would guarantee the control for many confounding factors.

  10. Optimized Discretization Schemes For Brain Images

    Directory of Open Access Journals (Sweden)

    USHA RANI.N,

    2011-02-01

    Full Text Available In medical image processing active contour method is the important technique in segmenting human organs. Geometric deformable curves known as levelsets are widely used in segmenting medical images. In this modeling , evolution of the curve is described by the basic lagrange pde expressed as a function of space and time. This pde can be solved either using continuous functions or discrete numerical methods.This paper deals with the application of numerical methods like finite diffefence and TVd-RK methods for brain scans. The stability and accuracy of these methods are also discussed. This paper also deals with the more accurate higher order non-linear interpolation techniques like ENO and WENO in reconstructing the brain scans like CT,MRI,PET and SPECT is considered.

  11. Brain SPECT imaging in Sydenham's chorea

    Directory of Open Access Journals (Sweden)

    Barsottini O.G.P.

    2002-01-01

    Full Text Available The objective of the present study was to determine whether brain single-photon emission computed tomography (SPECT imaging is capable of detecting perfusional abnormalities. Ten Sydenham's chorea (SC patients, eight females and two males, 8 to 25 years of age (mean 13.4, with a clinical diagnosis of SC were submitted to brain SPECT imaging. We used HMPAO labeled with technetium-99m at a dose of 740 MBq. Six examinations revealed hyperperfusion of the basal ganglia, while the remaining four were normal. The six patients with abnormal results were females and their data were not correlated with severity of symptoms. Patients with abnormal brain SPECT had a more recent onset of symptoms (mean of 49 days compared to those with normal SPECT (mean of 85 days but this difference did not reach statistical significance. Brain SPECT can be a helpful method to determine abnormalities of the basal ganglia in SC patients but further studies on a larger number of patients are needed in order to detect the phase of the disease during which the examination is more sensitive.

  12. Thermoacoustic tomography arising in brain imaging

    CERN Document Server

    Stefanov, Plamen

    2010-01-01

    We study the mathematical model of thermoacoustic and photoacoustic tomography when the sound speed has a jump across a smooth surface. This models the change of the sound speed in the skull when trying to image the human brain. We derive an explicit inversion formula in the form of a convergent Neumann series under the assumptions that all singularities from the support of the source reach the boundary.

  13. Non-FDG PET imaging of brain tumors

    Institute of Scientific and Technical Information of China (English)

    HUANG Zemin; GUAN Yihui; ZUO Chuantao; ZHANG Zhengwei; XUE Fangping; LIN Xiangtong

    2007-01-01

    Due to relatively high uptake of glucose in the brain cortex, the use of FDG PET imaging is greatly limited in brain tumor imaging, especially for low-grade gliomas and some metastatic tumours. More and more tracers with higher specificity were developed lately for brain tumor imaging. There are 3 main types of non-FDG PET tracers:amino acid tracers, choline tracers and nucleic acid tracers. These tracers are now widely applied in many aspects of brain tumor imaging. This article summarized the general use of non-FDG PET in different aspects of brain tumor imaging.

  14. Chitosan-based formulations of drugs, imaging agents and biotherapeutics

    NARCIS (Netherlands)

    Amidi, M.; Hennink, W.E.

    2010-01-01

    This preface is part of the Advanced Drug Delivery Reviews theme issue on “Chitosan-Based Formulations of Drugs, Imaging Agents and Biotherapeutics”. This special Advanced Drug Delivery Reviews issue summarizes recent progress and different applications of chitosanbased formulations.

  15. Fetal trauma: brain imaging in four neonates

    Energy Technology Data Exchange (ETDEWEB)

    Breysem, Luc; Mussen, E.; Demaerel, P.; Smet, M. [Department of Radiology, University Hospitals, Herestraat 49, 3000, Leuven (Belgium); Cossey, V. [Department of Pediatrics, University Hospitals, Leuven (Belgium); Voorde, W. van de [Department of Forensic Medicine, University Hospitals, Leuven (Belgium)

    2004-09-01

    The purpose of this paper is to describe brain pathology in neonates after major traffic trauma in utero during the third trimester. Our patient cohort consisted of four neonates born by emergency cesarean section after car accident in the third trimester of pregnancy. The median gestational age (n=4) was 36 weeks (range: 30-38). Immediate post-natal and follow-up brain imaging consisted of cranial ultrasound (n=4), computed tomography (CT) (n=1) and post-mortem magnetic resonance imaging (MRI) (n=1). Pathology findings were correlated with the imaging findings (n=3). Cranial ultrasound demonstrated a huge subarachnoidal hemorrhage (n=1), subdural hematoma (n=1), brain edema with inversion of the diastolic flow (n=1) and severe ischemic changes (n=1). In one case, CT demonstrated the presence and extension of the subarachnoidal hemorrhage, a parietal fracture and a limited intraventricular hemorrhage. Cerebellar hemorrhage and a small cerebral frontal contusion were seen on post-mortem MRI in a child with a major subarachnoidal hemorrhage on ultrasound. None of these four children survived (three children died within 2 days and one child died after 1 month). Blunt abdominal trauma during pregnancy can cause fetal cranial injury. In our cases, skull fracture, intracranial hemorrhage and hypoxic-ischemic encephalopathy were encountered. (orig.)

  16. Cerebral infarction mimicking brain tumor on Tc-99m tetrofosmin brain SPECT imaging

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Soon [College of Medicine, Dongguk Univ., Gyeongju (Korea, Republic of); Zeon, Seok Kil; Won, Kyoung Sook [School of Medicine, Keimyung Univ., Daegu (Korea, Republic of)

    2004-06-01

    A 43-year-old man was presented with persistent headache for two weeks. T2 weighted MR imaging showed high signal intensity with surrounding edema in the left frontal lobe. These findings were considered with intracranial tumor such as glioma or metastasis. Tc-99m tetrofosmin SPECT showed focal radiotracer accumulation in the left frontal lobe. The operative specimen contained cerebral infarction with organizing leptomeningeal hematoma by pathologist. Another 73-year-old man was hospitalized for chronic headache. Initial CT showed ill-defined hypodensity with mass effect in the right parietal lobe. Tc-99m tetrofosmin SPECT showed focal radiotracer uptake in the right parietal lobe. These findings were considered with low-grade glioma or infarction. Follow-up CT after 5 months showed slightly decreased in size of low density in the right parietal lobe, and cerebral infarction is more likely than others. Tc-99m tetrofosmin has been proposed as a cardiotracer of myocardial perfusion imaging and an oncotropic radiotracer. Tc-99 tetrofosmin SPECT image provides a better attractive alternative agent than TI-201 as a tumor-imaging agent, with characteristics such as high-energy flux, short half-life, favorable biodistribution, dosimetry and lower background radioactivity. We have keep in mind on the analysis of Tc-99m tetrofosmin imaging when cerebral infarction is being differentiated from brain tumor.

  17. Contrast Agents for Photoacoustic and Thermoacoustic Imaging: A Review

    Directory of Open Access Journals (Sweden)

    Dan Wu

    2014-12-01

    Full Text Available Photoacoustic imaging (PAI and thermoacoustic imaging (TAI are two emerging biomedical imaging techniques that both utilize ultrasonic signals as an information carrier. Unique advantages of PAI and TAI are their abilities to provide high resolution functional information such as hemoglobin and blood oxygenation and tissue dielectric properties relevant to physiology and pathology. These two methods, however, may have a limited detection depth and lack of endogenous contrast. An exogenous contrast agent is often needed to effectively resolve these problems. Such agents are able to greatly enhance the imaging contrast and potentially break through the imaging depth limit. Furthermore, a receptor-targeted contrast agent could trace the molecular and cellular biological processes in tissues. Thus, photoacoustic and thermoacoustic molecular imaging can be outstanding tools for early diagnosis, precise lesion localization, and molecular typing of various diseases. The agents also could be used for therapy in conjugation with drugs or in photothermal therapy, where it functions as an enhancer for the integration of diagnosis and therapy. In this article, we present a detailed review about various exogenous contrast agents for photoacoustic and thermoacoustic molecular imaging. In addition, challenges and future directions of photoacoustic and thermoacoustic molecular imaging in the field of translational medicine are also discussed.

  18. Contrast agents for photoacoustic and thermoacoustic imaging: a review.

    Science.gov (United States)

    Wu, Dan; Huang, Lin; Jiang, Max S; Jiang, Huabei

    2014-12-18

    Photoacoustic imaging (PAI) and thermoacoustic imaging (TAI) are two emerging biomedical imaging techniques that both utilize ultrasonic signals as an information carrier. Unique advantages of PAI and TAI are their abilities to provide high resolution functional information such as hemoglobin and blood oxygenation and tissue dielectric properties relevant to physiology and pathology. These two methods, however, may have a limited detection depth and lack of endogenous contrast. An exogenous contrast agent is often needed to effectively resolve these problems. Such agents are able to greatly enhance the imaging contrast and potentially break through the imaging depth limit. Furthermore, a receptor-targeted contrast agent could trace the molecular and cellular biological processes in tissues. Thus, photoacoustic and thermoacoustic molecular imaging can be outstanding tools for early diagnosis, precise lesion localization, and molecular typing of various diseases. The agents also could be used for therapy in conjugation with drugs or in photothermal therapy, where it functions as an enhancer for the integration of diagnosis and therapy. In this article, we present a detailed review about various exogenous contrast agents for photoacoustic and thermoacoustic molecular imaging. In addition, challenges and future directions of photoacoustic and thermoacoustic molecular imaging in the field of translational medicine are also discussed.

  19. Neurosurgical confocal endomicroscopy: A review of contrast agents, confocal systems, and future imaging modalities

    Directory of Open Access Journals (Sweden)

    Aqib H Zehri

    2014-01-01

    Full Text Available Background: The clinical application of fluorescent contrast agents (fluorescein, indocyanine green, and aminolevulinic acid with intraoperative microscopy has led to advances in intraoperative brain tumor imaging. Their properties, mechanism of action, history of use, and safety are analyzed in this report along with a review of current laser scanning confocal endomicroscopy systems. Additional imaging modalities with potential neurosurgical utility are also analyzed. Methods: A comprehensive literature search was performed utilizing PubMed and key words: In vivo confocal microscopy, confocal endomicroscopy, fluorescence imaging, in vivo diagnostics/neoplasm, in vivo molecular imaging, and optical imaging. Articles were reviewed that discussed clinically available fluorophores in neurosurgery, confocal endomicroscopy instrumentation, confocal microscopy systems, and intraoperative cancer diagnostics. Results: Current clinically available fluorescent contrast agents have specific properties that provide microscopic delineation of tumors when imaged with laser scanning confocal endomicroscopes. Other imaging modalities such as coherent anti-Stokes Raman scattering (CARS microscopy, confocal reflectance microscopy, fluorescent lifetime imaging (FLIM, two-photon microscopy, and second harmonic generation may also have potential in neurosurgical applications. Conclusion: In addition to guiding tumor resection, intraoperative fluorescence and microscopy have the potential to facilitate tumor identification and complement frozen section analysis during surgery by providing real-time histological assessment. Further research, including clinical trials, is necessary to test the efficacy of fluorescent contrast agents and optical imaging instrumentation in order to establish their role in neurosurgery.

  20. The effect of blood brain barrier modulation on oxime efficacy in nerve agent poisoning (Abstract)

    NARCIS (Netherlands)

    Joosen, M.; Schans, M.J. van der; Dijk, C.G.M. van; Kuijpers, WC.; Wortelboer, H.M.; Helden, H.P.M. van

    2012-01-01

    One of the shortcomings of current treatment of nerve agent poisoning is that oximes hardly penetrate the blood brain barrier (BBB), whereas nerve agents easily do. Enhancing the efficacy of current oximes in the brain, would therefore provide an attractive approach to improve medical countermeasure

  1. Multifunctional ultrasound contrast agents for imaging guided photothermal therapy.

    Science.gov (United States)

    Guo, Caixin; Jin, Yushen; Dai, Zhifei

    2014-05-21

    Among all the imaging techniques, ultrasound imaging has a unique advantage due to its features of real-time, low cost, high safety, and portability. Ultrasound contrast agents (UCAs) have been widely used to enhance ultrasonic signals. One of the most exciting features of UCAs for use in biomedicine is the possibility of easily putting new combinations of functional molecules into microbubbles (MBs), which are the most routinely used UCAs. Various therapeutic agents and medical nanoparticles (quantum dots, gold, Fe3O4, etc.) can be loaded into ultrasound-responsive MBs. Hence, UCAs can be developed as multifunctional agents that integrate capabilities for early detection and diagnosis and for imaging guided therapy of various diseases. The current review will focus on such state-of-the-art UCA platforms that have been exploited for multimodal imaging and for imaging guided photothermal therapy.

  2. Radioiodinated glucose analogues for use as imaging agents

    Science.gov (United States)

    Goodman, Mark M.; Knapp, Jr., Furn F.

    1988-01-01

    A radioiodinated branched carbohydrate for tissue imaging. Iodine-123 is stabilized in the compound by attaching it to a vinyl functional group that is on the carbohydrate. The compound exhibits good uptake and retention and is promising in the development of radiopharmaceuticals for brain, heart and tumor imaging.

  3. Structural imaging measures of brain aging.

    Science.gov (United States)

    Lockhart, Samuel N; DeCarli, Charles

    2014-09-01

    During the course of normal aging, biological changes occur in the brain that are associated with changes in cognitive ability. This review presents data from neuroimaging studies of primarily "normal" or healthy brain aging. As such, we focus on research in unimpaired or nondemented older adults, but also include findings from lifespan studies that include younger and middle aged individuals as well as from populations with prodromal or clinically symptomatic disease such as cerebrovascular or Alzheimer's disease. This review predominantly addresses structural MRI biomarkers, such as volumetric or thickness measures from anatomical images, and measures of white matter injury and integrity respectively from FLAIR or DTI, and includes complementary data from PET and cognitive or clinical testing as appropriate. The findings reveal highly consistent age-related differences in brain structure, particularly frontal lobe and medial temporal regions that are also accompanied by age-related differences in frontal and medial temporal lobe mediated cognitive abilities. Newer findings also suggest that degeneration of specific white matter tracts such as those passing through the genu and splenium of the corpus callosum may also be related to age-related differences in cognitive performance. Interpretation of these findings, however, must be tempered by the fact that comorbid diseases such as cerebrovascular and Alzheimer's disease also increase in prevalence with advancing age. As such, this review discusses challenges related to interpretation of current theories of cognitive aging in light of the common occurrence of these later-life diseases. Understanding the differences between "Normal" and "Healthy" brain aging and identifying potential modifiable risk factors for brain aging is critical to inform potential treatments to stall or reverse the effects of brain aging and possibly extend cognitive health for our aging society.

  4. Spatial normalization of brain images and beyond.

    Science.gov (United States)

    Mangin, J-F; Lebenberg, J; Lefranc, S; Labra, N; Auzias, G; Labit, M; Guevara, M; Mohlberg, H; Roca, P; Guevara, P; Dubois, J; Leroy, F; Dehaene-Lambertz, G; Cachia, A; Dickscheid, T; Coulon, O; Poupon, C; Rivière, D; Amunts, K; Sun, Z Y

    2016-10-01

    The deformable atlas paradigm has been at the core of computational anatomy during the last two decades. Spatial normalization is the variant endowing the atlas with a coordinate system used for voxel-based aggregation of images across subjects and studies. This framework has largely contributed to the success of brain mapping. Brain spatial normalization, however, is still ill-posed because of the complexity of the human brain architecture and the lack of architectural landmarks in standard morphological MRI. Multi-atlas strategies have been developed during the last decade to overcome some difficulties in the context of segmentation. A new generation of registration algorithms embedding architectural features inferred for instance from diffusion or functional MRI is on the verge to improve the architectural value of spatial normalization. A better understanding of the architectural meaning of the cortical folding pattern will lead to use some sulci as complementary constraints. Improving the architectural compliance of spatial normalization may impose to relax the diffeomorphic constraint usually underlying atlas warping. A two-level strategy could be designed: in each region, a dictionary of templates of incompatible folding patterns would be collected and matched in a way or another using rare architectural information, while individual subjects would be aligned using diffeomorphisms to the closest template. Manifold learning could help to aggregate subjects according to their morphology. Connectivity-based strategies could emerge as an alternative to deformation-based alignment leading to match the connectomes of the subjects rather than images.

  5. Diffuse Optical Tomography for Brain Imaging: Theory

    Science.gov (United States)

    Yuan, Zhen; Jiang, Huabei

    Diffuse optical tomography (DOT) is a noninvasive, nonionizing, and inexpensive imaging technique that uses near-infrared light to probe tissue optical properties. Regional variations in oxy- and deoxy-hemoglobin concentrations as well as blood flow and oxygen consumption can be imaged by monitoring spatiotemporal variations in the absorption spectra. For brain imaging, this provides DOT unique abilities to directly measure the hemodynamic, metabolic, and neuronal responses to cells (neurons), and tissue and organ activations with high temporal resolution and good tissue penetration. DOT can be used as a stand-alone modality or can be integrated with other imaging modalities such as fMRI/MRI, PET/CT, and EEG/MEG in studying neurophysiology and pathology. This book chapter serves as an introduction to the basic theory and principles of DOT for neuroimaging. It covers the major aspects of advances in neural optical imaging including mathematics, physics, chemistry, reconstruction algorithm, instrumentation, image-guided spectroscopy, neurovascular and neurometabolic coupling, and clinical applications.

  6. 64Cu loaded liposomes as positron emission tomography imaging agents

    DEFF Research Database (Denmark)

    Petersen, Anncatrine Luisa; Binderup, Tina; Rasmussen, Palle;

    2011-01-01

    We have developed a highly efficient method for utilizing liposomes as imaging agents for positron emission tomography (PET) giving high resolution images and allowing direct quantification of tissue distribution and blood clearance. Our approach is based on remote loading of a copper-radionuclid...

  7. Image reconstruction techniques for high resolution human brain PET imaging

    Energy Technology Data Exchange (ETDEWEB)

    Comtat, C.; Bataille, F.; Sureau, F. [Service Hospitalier Frederic Joliot (CEA/DSV/DRM), 91 - Orsay (France)

    2006-07-01

    High resolution PET imaging is now a well established technique not only for small animal, but also for human brain studies. The ECAT HRRT brain PET scanner(Siemens Molecular Imaging) is characterized by an effective isotropic spatial resolution of 2.5 mm, about a factor of 2 better than for state-of-the-art whole-body clinical PET scanners. Although the absolute sensitivity of the HRRT (6.5 %) for point source in the center of the field-of-view is increased relative to whole-body scanner (typically 4.5 %) thanks to a larger co-polar aperture, the sensitivity in terms of volumetric resolution (75 (m{sup 3} at best for whole-body scanners and 16 (m{sup 3} for t he HRRT) is much lower. This constraint has an impact on the performance of image reconstruction techniques, in particular for dynamic studies. Standard reconstruction methods used with clinical whole-body PET scanners are not optimal for this application. Specific methods had to be developed, based on fully 3D iterative techniques. Different refinements can be added in the reconstruction process to improve image quality: more accurate modeling of the acquisition system, more accurate modeling of the statistical properties of the acquired data, anatomical side information to guide the reconstruction . We will present the performances these added developments for neuronal imaging in humans. (author)

  8. Susceptibility weighted imaging of the neonatal brain

    Energy Technology Data Exchange (ETDEWEB)

    Meoded, A.; Poretti, A. [Division of Pediatric Radiology and Division of Neuroradiology, Russell H. Morgan Department of Radiology and Radiological Sciences, Johns Hopkins University School of Medicine, Baltimore, MD (United States); Northington, F.J. [Division of Neonatology, Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, MD (United States); Tekes, A.; Intrapiromkul, J. [Division of Pediatric Radiology and Division of Neuroradiology, Russell H. Morgan Department of Radiology and Radiological Sciences, Johns Hopkins University School of Medicine, Baltimore, MD (United States); Huisman, T.A.G.M., E-mail: thuisma1@jhmi.edu [Division of Pediatric Radiology and Division of Neuroradiology, Russell H. Morgan Department of Radiology and Radiological Sciences, Johns Hopkins University School of Medicine, Baltimore, MD (United States)

    2012-08-15

    Susceptibility weighted imaging (SWI) is a well-established magnetic resonance technique, which is highly sensitive for blood, iron, and calcium depositions in the brain and has been implemented in the routine clinical use in both children and neonates. SWI in neonates might provide valuable additional diagnostic and prognostic information for a wide spectrum of neonatal neurological disorders. To date, there are few articles available on the application of SWI in neonatal neurological disorders. The purpose of this article is to illustrate and describe the characteristic SWI findings in various typical neonatal neurological disorders.

  9. Multifunctional Photosensitizer-Based Contrast Agents for Photoacoustic Imaging

    Science.gov (United States)

    Ho, Chris Jun Hui; Balasundaram, Ghayathri; Driessen, Wouter; McLaren, Ross; Wong, Chi Lok; Dinish, U. S.; Attia, Amalina Binte Ebrahim; Ntziachristos, Vasilis; Olivo, Malini

    2014-06-01

    Photoacoustic imaging is a novel hybrid imaging modality combining the high spatial resolution of optical imaging with the high penetration depth of ultrasound imaging. Here, for the first time, we evaluate the efficacy of various photosensitizers that are widely used as photodynamic therapeutic (PDT) agents as photoacoustic contrast agents. Photoacoustic imaging of photosensitizers exhibits advantages over fluorescence imaging, which is prone to photobleaching and autofluorescence interference. In this work, we examined the photoacoustic activity of 5 photosensitizers: zinc phthalocyanine, protoporphyrin IX, 2,4-bis [4-(N,N-dibenzylamino)-2,6-dihydroxyphenyl] squaraine, chlorin e6 and methylene blue in phantoms, among which zinc phthalocyanine showed the highest photoacoustic activity. Subsequently, we evaluated its tumor localization efficiency and biodistribution at multiple time points in a murine model using photoacoustic imaging. We observed that the probe localized at the tumor within 10 minutes post injection, reaching peak accumulation around 1 hour and was cleared within 24 hours, thus, demonstrating the potential of photosensitizers as photoacoustic imaging contrast agents in vivo. This means that the known advantages of photosensitizers such as preferential tumor uptake and PDT efficacy can be combined with photoacoustic imaging capabilities to achieve longitudinal monitoring of cancer progression and therapy in vivo.

  10. Multifunctional photosensitizer-based contrast agents for photoacoustic imaging.

    Science.gov (United States)

    Ho, Chris Jun Hui; Balasundaram, Ghayathri; Driessen, Wouter; McLaren, Ross; Wong, Chi Lok; Dinish, U S; Attia, Amalina Binte Ebrahim; Ntziachristos, Vasilis; Olivo, Malini

    2014-06-18

    Photoacoustic imaging is a novel hybrid imaging modality combining the high spatial resolution of optical imaging with the high penetration depth of ultrasound imaging. Here, for the first time, we evaluate the efficacy of various photosensitizers that are widely used as photodynamic therapeutic (PDT) agents as photoacoustic contrast agents. Photoacoustic imaging of photosensitizers exhibits advantages over fluorescence imaging, which is prone to photobleaching and autofluorescence interference. In this work, we examined the photoacoustic activity of 5 photosensitizers: zinc phthalocyanine, protoporphyrin IX, 2,4-bis [4-(N,N-dibenzylamino)-2,6-dihydroxyphenyl] squaraine, chlorin e6 and methylene blue in phantoms, among which zinc phthalocyanine showed the highest photoacoustic activity. Subsequently, we evaluated its tumor localization efficiency and biodistribution at multiple time points in a murine model using photoacoustic imaging. We observed that the probe localized at the tumor within 10 minutes post injection, reaching peak accumulation around 1 hour and was cleared within 24 hours, thus, demonstrating the potential of photosensitizers as photoacoustic imaging contrast agents in vivo. This means that the known advantages of photosensitizers such as preferential tumor uptake and PDT efficacy can be combined with photoacoustic imaging capabilities to achieve longitudinal monitoring of cancer progression and therapy in vivo.

  11. {sup 18}F-labeled styrylpyridines as PET agents for amyloid plaque imaging

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Wei [Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104 (United States); Kung Meip ing [Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104 (United States); Oya, Shunichi [Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104 (United States); Hou, Catherine [Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104 (United States); Kung, Hank F. [Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104 (United States)]. E-mail: kunghf@sunmac.spect.upenn.edu

    2007-01-15

    Positron emission tomography (PET) imaging of {beta}-amyloid (A{beta}) plaques in the brain is a potentially valuable tool for studying the pathophysiology of Alzheimer's disease (AD). It may also be applicable for measuring the effectiveness of therapeutic drugs aimed at lowering A{beta} plaques in the brain. We have successfully reported a series of {sup 18}F-labeled fluoropegylated stilbenes for PET imaging studies. Encouraging results clearly demonstrated the usefulness of {sup 18}F-labeled stilbenes as potential A{beta} plaque-imaging agents. In the present study, we applied a similar approach to a styrylpyridine backbone structure. Among all derivatives examined (E)-2-(2-(2-(2-fluoroethoxy)ethoxy)ethoxy)-5-(4-dimethylaminostyryl) -pyridine (2) displayed high binding affinity in postmortem AD brain homogenates (K {sub i}=2.5{+-}0.4 nM, with [{sup 125}I]IMPY as radioligand). No-carrier-added [{sup 18}F]2 was successfully prepared by [{sup 18}F]fluoride displacement of the corresponding tosylate precursor with a high labeling yield (30-40%) and a high radiochemical purity (>99%). Specific activity at the end of synthesis was determined to be 1500-2000 Ci/mmol. The tracer [{sup 18}F]2 showed adequate lipophilicity (log P=3.22). In vivo biodistribution of [{sup 18}F]2 in normal mice exhibited excellent initial brain penetration and rapid washout (7.77% and 1.03% dose/g in the brain at 2 and 30 min after intravenous injection, respectively) - properties that are highly desirable for A{beta}-plaque-specific brain imaging agents. Autoradiography of AD brain sections and homogenate binding with postmortem AD brain tissues confirmed the high binding signal of [{sup 18}F]2 due to the presence of A{beta} plaques. These preliminary results suggest that novel PET tracers may be potentially useful for the imaging of A{beta} plaques in the living human brain.

  12. Neurolight -astonishing advances in brain imaging.

    Science.gov (United States)

    Rojczyk-Gołębiewska, Ewa; Pałasz, Artur; Worthington, John J; Markowski, Grzegorz; Wiaderkiewicz, Ryszard

    2015-02-01

    In recent years, significant advances in basic neuroanatomical studies have taken place. Moreover, such classical, clinically-oriented human brain imaging methods such as MRI, PET and DTI have been applied to small laboratory animals allowing improvement in current experimental neuroscience. Contemporary structural neurobiology also uses various technologies based on fluorescent proteins. One of these is optogenetics, which integrates physics, genetics and bioengineering to enable temporal precise control of electrical activity of specific neurons. Another important challenge in the field is the accurate imaging of complicated neural networks. To address this problem, three-dimensional reconstruction techniques and retrograde labeling with modified viruses has been developed. However, a revolutionary step was the invention of the "Brainbow" system, utilizing gene constructs including the sequences of fluorescent proteins and the usage of Cre recombinase to create dozens of colour combinations, enabling visualization of neurons and their connections in extremely high resolution. Furthermore, the newly- introduced CLARITY method should make it possible to visualize three-dimensionally the structure of translucent brain tissue using the hydrogel polymeric network. This original technique is a big advance in neuroscience creating novel viewpoints completely different than standard glass slide immunostaining.

  13. Biocompatible KMnF3 nanoparticular contrast agent with proper plasma retention time for in vivo magnetic resonance imaging.

    Science.gov (United States)

    Liu, Zhi-jun; Song, Xiao-xia; Xu, Xian-zhu; Tang, Qun

    2014-04-18

    Nanoparticular MRI contrast agents are rapidly becoming suitable for use in clinical diagnosis. An ideal nanoparticular contrast agent should be endowed with high relaxivity, biocompatibility, proper plasma retention time, and tissue-specific or tumor-targeting imaging. Herein we introduce PEGylated KMnF3 nanoparticles as a new type of T1 contrast agent. Studies showed that the nanoparticular contrast agent revealed high bio-stability with bovine serum albumin in PBS buffer solution, and presented excellent biocompatibility (low cytotoxicity, undetectable hemolysis and hemagglutination). Meanwhile the new contrast agent possessed proper plasma retention time (circulation half-life t1/2 is approximately 2 h) in the body of the administrated mice. It can be delivered into brain vessels and maintained there for hours, and is mostly cleared from the body within 48 h, as demonstrated by time-resolved MRI and Mn-biodistribution analysis. Those distinguishing features make it suitable to obtain contrast-enhanced brain magnetic resonance angiography. Moreover, through the process of passive targeting delivery, the T1 contrast agent clearly illuminates a brain tumor (glioma) with high contrast image and defined shape. This study demonstrates that PEGylated KMnF3 nanoparticles represent a promising biocompatible vascular contrast agent for magnetic resonance angiography and can potentially be further developed into an active targeted tumor MRI contrast agent.

  14. Contrast Agent in Magnetic Resonance Imaging

    DEFF Research Database (Denmark)

    Vu-Quang, Hieu

    2015-01-01

    formulated in order to suppress inflamed cytokine expression by siRNA transfection as well as following the migration of macrophage using MRI and NIR bio-imaging. The nano-complexes could inhibit 50 % mRNA expression and 39 % protein expression. In the in vivo cell tracking NIR bio-imaging and MRI...... for chemotherapy. The nanoparticles were 150 nm in size with spherical shape, which contained PFOB in the inner core and Dox and ICG in the polymeric shell. More importantly, they could target folate receptor expressing cancer cells, which provide positive in vitro and in vivo NIR and 19F MRI results. In project...... stem cells and Raw 264.7 macrophages were chitosan-to-particles weight ratios of w0.1 and w0.01, respectively. In vivo 19F MRI results showed the possibility of capturing labeled cells indicating the potential use of PLGA PFOB in future research involving such as cell migration. . In regard of magnetic...

  15. Compact and mobile high resolution PET brain imager

    Science.gov (United States)

    Majewski, Stanislaw; Proffitt, James

    2011-02-08

    A brain imager includes a compact ring-like static PET imager mounted in a helmet-like structure. When attached to a patient's head, the helmet-like brain imager maintains the relative head-to-imager geometry fixed through the whole imaging procedure. The brain imaging helmet contains radiation sensors and minimal front-end electronics. A flexible mechanical suspension/harness system supports the weight of the helmet thereby allowing for patient to have limited movements of the head during imaging scans. The compact ring-like PET imager enables very high resolution imaging of neurological brain functions, cancer, and effects of trauma using a rather simple mobile scanner with limited space needs for use and storage.

  16. Infrared Imaging System for Studying Brain Function

    Science.gov (United States)

    Mintz, Frederick; Mintz, Frederick; Gunapala, Sarath

    2007-01-01

    A proposed special-purpose infrared imaging system would be a compact, portable, less-expensive alternative to functional magnetic resonance imaging (fMRI) systems heretofore used to study brain function. Whereas a typical fMRI system fills a large room, and must be magnetically isolated, this system would fit into a bicycle helmet. The system would include an assembly that would be mounted inside the padding in a modified bicycle helmet or other suitable headgear. The assembly would include newly designed infrared photodetectors and data-acquisition circuits on integrated-circuit chips on low-thermal-conductivity supports in evacuated housings (see figure) arranged in multiple rows and columns that would define image coordinates. Each housing would be spring-loaded against the wearer s head. The chips would be cooled by a small Stirling Engine mounted contiguous to, but thermally isolated from, the portions of the assembly in thermal contact with the wearer s head. Flexible wires or cables for transmitting data from the aforementioned chips would be routed to an integrated, multichannel transmitter and thence through the top of the assembly to a patch antenna on the outside of the helmet. The multiple streams of data from the infrared-detector chips would be sent to a remote site, where they would be processed, by software, into a three-dimensional display of evoked potentials that would represent firing neuronal bundles and thereby indicate locations of neuronal activity associated with mental or physical activity. The 3D images will be analogous to current fMRI images. The data would also be made available, in real-time, for comparison with data in local or internationally accessible relational databases that already exist in universities and research centers. Hence, this system could be used in research on, and for the diagnosis of response from the wearer s brain to physiological, psychological, and environmental changes in real time. The images would also be

  17. 4-haloethenylphenyl tropane:serotonin transporter imaging agents

    Science.gov (United States)

    Goodman, Mark M.; Martarello, Laurent

    2005-01-18

    A series of compounds in the 4-fluoroalkyl-3-halophenyl nortropanes and 4-haloethenylphenyl tropane families are described as diagnostic and therapeutic agents for diseases associated with serotonin transporter dysfunction. These compounds bind to serotonin transporter protein with high affinity and selectivity. The invention provides methods of synthesis which incorporate radioisotopic halogens at a last step which permit high radiochemical yield and maximum usable product life. The radiolabeled compounds of the invention are useful as imaging agents for visualizing the location and density of serotonin transporter by PET and SPECT imaging.

  18. FULLY AUTOMATIC FRAMEWORK FOR SEGMENTATION OF BRAIN MRI IMAGE

    Institute of Scientific and Technical Information of China (English)

    Lin Pan; Zheng Chongxun; Yang Yong; Gu Jianwen

    2005-01-01

    Objective To propose an automatic framework for segmentation of brain image in this paper. Methods The brain MRI image segmentation framework consists of three-step segmentation procedures. First, Non-brain structures removal by level set method. Then, the non-uniformity correction method is based on computing estimates of tissue intensity variation. Finally, it uses a statistical model based on Markov random filed for MRI brain image segmentation. The brain tissue can be classified into cerebrospinal fluid, white matter and gray matter. Results To evaluate the proposed our method, we performed two sets of experiments, one on simulated MR and another on real MR brain data. Conclusion The efficacy of the brain MRI image segmentation framework has been demonstrated by the extensive experiments. In the future, we are also planning on a large-scale clinical evaluation of this segmentation framework.

  19. Calcium imaging of infrared-stimulated activity in rodent brain.

    Science.gov (United States)

    Cayce, Jonathan Matthew; Bouchard, Matthew B; Chernov, Mykyta M; Chen, Brenda R; Grosberg, Lauren E; Jansen, E Duco; Hillman, Elizabeth M C; Mahadevan-Jansen, Anita

    2014-04-01

    Infrared neural stimulation (INS) is a promising neurostimulation technique that can activate neural tissue with high spatial precision and without the need for exogenous agents. However, little is understood about how infrared light interacts with neural tissue on a cellular level, particularly within the living brain. In this study, we use calcium sensitive dye imaging on macroscopic and microscopic scales to explore the spatiotemporal effects of INS on cortical calcium dynamics. The INS-evoked calcium signal that was observed exhibited a fast and slow component suggesting activation of multiple cellular mechanisms. The slow component of the evoked signal exhibited wave-like properties suggesting network activation, and was verified to originate from astrocytes through pharmacology and 2-photon imaging. We also provide evidence that the fast calcium signal may have been evoked through modulation of glutamate transients. This study demonstrates that pulsed infrared light can induce intracellular calcium modulations in both astrocytes and neurons, providing new insights into the mechanisms of action of INS in the brain.

  20. FCM Clustering Algorithms for Segmentation of Brain MR Images

    Directory of Open Access Journals (Sweden)

    Yogita K. Dubey

    2016-01-01

    Full Text Available The study of brain disorders requires accurate tissue segmentation of magnetic resonance (MR brain images which is very important for detecting tumors, edema, and necrotic tissues. Segmentation of brain images, especially into three main tissue types: Cerebrospinal Fluid (CSF, Gray Matter (GM, and White Matter (WM, has important role in computer aided neurosurgery and diagnosis. Brain images mostly contain noise, intensity inhomogeneity, and weak boundaries. Therefore, accurate segmentation of brain images is still a challenging area of research. This paper presents a review of fuzzy c-means (FCM clustering algorithms for the segmentation of brain MR images. The review covers the detailed analysis of FCM based algorithms with intensity inhomogeneity correction and noise robustness. Different methods for the modification of standard fuzzy objective function with updating of membership and cluster centroid are also discussed.

  1. Software Agent with Reinforcement Learning Approach for Medical Image Segmentation

    Institute of Scientific and Technical Information of China (English)

    Mahsa Chitsaz; Chaw Seng Woo

    2011-01-01

    Many image segmentation solutions are problem-based. Medical images have very similar grey level and texture among the interested objects. Therefore, medical image segmentation requires improvements although there have been researches done since the last few decades. We design a self-learning framework to extract several objects of interest simultaneously from Computed Tomography (CT) images. Our segmentation method has a learning phase that is based on reinforcement learning (RL) system. Each RL agent works on a particular sub-image of an input image to find a suitable value for each object in it. The RL system is define by state, action and reward. We defined some actions for each state in the sub-image. A reward function computes reward for each action of the RL agent. Finally, the valuable information, from discovering all states of the interest objects, will be stored in a Q-matrix and the final result can be applied in segmentation of similar images. The experimental results for cranial CT images demonstrated segmentation accuracy above 95%.

  2. Fluorescence microscopy studies of a peripheral-benzodiazepine-receptor-targeted molecular probe for brain tumor imaging

    Science.gov (United States)

    Marcu, Laura; Vernier, P. Thomas; Manning, H. Charles; Salemi, Sarah; Li, Aimin; Craft, Cheryl M.; Gundersen, Martin A.; Bornhop, Darryl J.

    2003-10-01

    This study investigates the potential of a new multi-modal lanthanide chelate complex for specifically targeting brain tumor cells. We report here results from ongoing studies of up-take, sub-cellular localization and binding specificity of this new molecular imaging probe. Fluorescence microscopy investigations in living rat C6 glioma tumor cells demonstrate that the new imaging agent has affinity for glioma cells and binds to mitochondria.

  3. Metal-organic frameworks as sensory materials and imaging agents.

    Science.gov (United States)

    Liu, Demin; Lu, Kuangda; Poon, Christopher; Lin, Wenbin

    2014-02-17

    Metal-organic frameworks (MOFs) are a class of hybrid materials self-assembled from organic bridging ligands and metal ion/cluster connecting points. The combination of a variety of organic linkers, metal ions/clusters, and structural motifs can lead to an infinite array of new materials with interesting properties for many applications. In this Forum Article, we discuss the design and applications of MOFs in chemical sensing and biological imaging. The first half of this article focuses on the development of MOFs as chemical sensors by highlighting how unique attributes of MOFs can be utilized to enhance sensitivity and selectivity. We also discuss some of the issues that need to be addressed in order to develop practically useful MOF sensors. The second half of this article focuses on the design and applications of nanoscale MOFs (NMOFs) as imaging contrast agents. NMOFs possess several interesting attributes, such as high cargo loading capacity, ease of postmodification, tunable size and shape, and intrinsic biodegradability, to make them excellent candidates as imaging contrast agents. We discuss the use of representative NMOFs in magnetic resonance imaging (MRI), X-ray computed tomography (CT), and optical imaging. Although still in their infancy, we believe that the compositional tunability and mild synthetic conditions of NMOF imaging agents should greatly facilitate their further development for clinical translation.

  4. Consistent Reconstruction of Cortical Surfaces from Longitudinal Brain MR Images

    OpenAIRE

    Li, Gang; Nie, Jingxin; Wu, Guorong; Wang, Yaping; Shen, Dinggang

    2011-01-01

    Accurate and consistent reconstruction of cortical surfaces from longitudinal human brain MR images is of great importance in studying longitudinal subtle change of the cerebral cortex. This paper presents a novel deformable surface method for consistent and accurate reconstruction of inner, central and outer cortical surfaces from longitudinal brain MR images. Specifically, the cortical surfaces of the group-mean image of all aligned longitudinal images of the same subject are first reconstr...

  5. Optical Brain Imaging: A Powerful Tool for Neuroscience.

    Science.gov (United States)

    Zhu, Xinpei; Xia, Yanfang; Wang, Xuecen; Si, Ke; Gong, Wei

    2017-02-01

    As the control center of organisms, the brain remains little understood due to its complexity. Taking advantage of imaging methods, scientists have found an accessible approach to unraveling the mystery of neuroscience. Among these methods, optical imaging techniques are widely used due to their high molecular specificity and single-molecule sensitivity. Here, we overview several optical imaging techniques in neuroscience of recent years, including brain clearing, the micro-optical sectioning tomography system, and deep tissue imaging.

  6. Transport of nanoparticles through the blood-brain barrier for imaging and therapeutic applications

    Science.gov (United States)

    Shilo, Malka; Motiei, Menachem; Hana, Panet; Popovtzer, Rachela

    2014-01-01

    A critical problem in the treatment of neurodegenerative disorders and diseases, such as Alzheimer's and Parkinson's, is the incapability to overcome the restrictive mechanism of the blood-brain barrier (BBB) and to deliver important therapeutic agents to the brain. During the last decade, nanoparticles have gained attention as promising drug delivery agents that can transport across the BBB and increase the uptake of appropriate drugs in the brain. In this study we have developed insulin-targeted gold nanoparticles (INS-GNPs) and investigated quantitatively the amount of INS-GNPs that cross the BBB by the receptor-mediated endocytosis process. For this purpose, INS-GNPs and control GNPs were injected into the tail vein of male BALB/c mice. Major organs were then extracted and a blood sample was taken from the mice, and thereafter analyzed for gold content by flame atomic absorption spectroscopy. Results show that two hours post-intravenous injection, the amount of INS-GNPs found in mouse brains is over 5 times greater than that of the control, untargeted GNPs. Results of further experimentation on a rat model show that INS-GNPs can also serve as CT contrast agents to highlight specific brain regions in which they accumulate. Due to the fact that they can overcome the restrictive mechanism of the BBB, this approach could be a potentially valuable tool, helping to confront the great challenge of delivering important imaging and therapeutic agents to the brain for detection and treatment of neurodegenerative disorders and diseases.

  7. Advanced Pediatric Brain Imaging Research and Training Program

    Science.gov (United States)

    2015-10-01

    online learning management system, by creating and implementing methods for converting the existing in- classroom educational BRAIN seminars into self...iii) the necessary skills to apply advanced MRI techniques to study brain injury, and to facilitate the diagnosis, management , and ultimately...Recent advances in pediatric magnetic resonance imaging (MRI) techniques are revolutionizing our understanding of brain injury, its potential for

  8. Modelling Brain Tissue using Magnetic Resonance Imaging

    DEFF Research Database (Denmark)

    Dyrby, Tim Bjørn

    2008-01-01

    Diffusion MRI, or diffusion weighted imaging (DWI), is a technique that measures the restricted diffusion of water molecules within brain tissue. Different reconstruction methods quantify water-diffusion anisotropy in the intra- and extra-cellular spaces of the neural environment. Fibre tracking...... tractography. Although probabilistic tractography currently holds great promise as a powerful non-invasive connectivity-measurement tool, its accuracy and limitations remain to be evaluated. Probabilistic tractography was assessed post mortem in an in vitro environment. Postmortem DWI benefits from...... environment differs from that of in vivo both due to a lowered environmental temperature and due to the fixation process itself. We argue that the perfusion fixation procedure employed in this thesis ensures that the postmortem tissue is as close to that of in vivo as possible. Different fibre reconstruction...

  9. Whole Mouse Brain Image Reconstruction from Serial Coronal Sections Using FIJI (ImageJ).

    Science.gov (United States)

    Paletzki, Ronald; Gerfen, Charles R

    2015-10-01

    Whole-brain reconstruction of the mouse enables comprehensive analysis of the distribution of neurochemical markers, the distribution of anterogradely labeled axonal projections or retrogradely labeled neurons projecting to a specific brain site, or the distribution of neurons displaying activity-related markers in behavioral paradigms. This unit describes a method to produce whole-brain reconstruction image sets from coronal brain sections with up to four fluorescent markers using the freely available image-processing program FIJI (ImageJ).

  10. Ultrasound imaging beyond the vasculature with new generation contrast agents.

    Science.gov (United States)

    Perera, Reshani H; Hernandez, Christopher; Zhou, Haoyan; Kota, Pavan; Burke, Alan; Exner, Agata A

    2015-01-01

    Current commercially available ultrasound contrast agents are gas-filled, lipid- or protein-stabilized microbubbles larger than 1 µm in diameter. Because the signal generated by these agents is highly dependent on their size, small yet highly echogenic particles have been historically difficult to produce. This has limited the molecular imaging applications of ultrasound to the blood pool. In the area of cancer imaging, microbubble applications have been constrained to imaging molecular signatures of tumor vasculature and drug delivery enabled by ultrasound-modulated bubble destruction. Recently, with the rise of sophisticated advancements in nanomedicine, ultrasound contrast agents, which are an order of magnitude smaller (100-500 nm) than their currently utilized counterparts, have been undergoing rapid development. These agents are poised to greatly expand the capabilities of ultrasound in the field of targeted cancer detection and therapy by taking advantage of the enhanced permeability and retention phenomenon of many tumors and can extravasate beyond the leaky tumor vasculature. Agent extravasation facilitates highly sensitive detection of cell surface or microenvironment biomarkers, which could advance early cancer detection. Likewise, when combined with appropriate therapeutic agents and ultrasound-mediated deployment on demand, directly at the tumor site, these nanoparticles have been shown to contribute to improved therapeutic outcomes. Ultrasound's safety profile, broad accessibility and relatively low cost make it an ideal modality for the changing face of healthcare today. Aided by the multifaceted nano-sized contrast agents and targeted theranostic moieties described herein, ultrasound can considerably broaden its reach in future applications focused on the diagnosis and staging of cancer.

  11. The physiological and biochemical bases of functional brain imaging

    OpenAIRE

    2007-01-01

    Functional brain imaging is based on the display of computer-derived images of changes in physiological and/or biochemical functions altered by activation or depression of local functional activities in the brain. This article reviews the physiological and biochemical mechanisms involved.

  12. Optical Methods and Instrumentation in Brain Imaging and Therapy

    CERN Document Server

    2013-01-01

    This book provides a comprehensive up-to-date review of optical approaches used in brain imaging and therapy. It covers a variety of imaging techniques including diffuse optical imaging, laser speckle imaging, photoacoustic imaging and optical coherence tomography. A number of laser-based therapeutic approaches are reviewed, including photodynamic therapy, fluorescence guided resection and photothermal therapy. Fundamental principles and instrumentation are discussed for each imaging and therapeutic technique. Represents the first publication dedicated solely to optical diagnostics and therapeutics in the brain Provides a comprehensive review of the principles of each imaging/therapeutic modality Reviews the latest advances in instrumentation for optical diagnostics in the brain Discusses new optical-based therapeutic approaches for brain diseases

  13. [Psychopathology of schizophrenia and brain imaging].

    Science.gov (United States)

    Gross, G; Huber, G

    2008-05-01

    separated from idiopathic schizophrenias as symptomatic by neurohistopathological findings of post mortem examinations and e.g. diagnosed as sporadic, atypical encephalitis. The cenesthetic type had a pilot function for the development of the BSC, because in its course the basic symptomatology determined as well the prodromes before the first psychotic episode, as after that the reversible postpsychotic basic stages respectively the irreversible pure defect syndromes, into which two thirds of cenesthetic schizophrenias terminate; then, because with this type the first time has been observed, that from initially quite uncharacteristic basic symptoms (BS) (level 1 BS), qualitatively peculiar basic symptoms (level 2 BS) and then distinct psychotic symptoms, i.e. bodily hallucinations arise; and because in patients with persisting pure deficiency syndromes neuromorphological changes in the sense of a basal ganglia syndrome could be proved. The clinical neuroradiological correlation study in 195 schizophrenic patients with slight residues or full remissions and 212 chronic schizophrenias as well as in 535 patients with organic psychosyndromes of different diagnostic groups reveal that brain imaging and biological-psychiatric research are only promising in close connection with clinical psychopathology and observation of the course, if they aim to assign certain structural or functional cerebral disturbances with certain clinical symptoms and syndromes. In this respect schizophrenic, schizoaffective and affective idiopathic psychosyndromes do not differ from somatically based psychoses in definable brain diseases. With functional-dynamic parameters the differentiation in process active and inactive stages has to be made guided by the actual clinical psychopathological syndrome at the moment of the collecting of the electroencephalographic, neurochemical, fMRI or PET findings. The reasons of inconsistencies of the EEG, PEG, CT, MRI, PET findings are analysed and it is shown that

  14. Whole-brain dynamic CT angiography and perfusion imaging

    Energy Technology Data Exchange (ETDEWEB)

    Orrison, W.W. [CHW Nevada Imaging Company, Nevada Imaging Centers, Spring Valley, Las Vegas, NV (United States); College of Osteopathic Medicine, Touro University Nevada, Henderson, NV (United States); Department of Health Physics and Diagnostic Sciences, University of Nevada Las Vegas, Las Vegas, NV (United States); Department of Medical Education, University of Nevada School of Medicine, Reno, NV (United States); Snyder, K.V.; Hopkins, L.N. [Department of Neurosurgery, Millard Fillmore Gates Circle Hospital, Buffalo, NY (United States); Roach, C.J. [School of Life Sciences, University of Nevada Las Vegas, Las Vegas, NV (United States); Advanced Medical Imaging and Genetics (Amigenics), Las Vegas, NV (United States); Ringdahl, E.N. [Department of Psychology, University of Nevada Las Vegas, Las Vegas, NV (United States); Nazir, R. [Shifa International Hospital, Islamabad (Pakistan); Hanson, E.H., E-mail: eric.hanson@amigenics.co [College of Osteopathic Medicine, Touro University Nevada, Henderson, NV (United States); Department of Health Physics and Diagnostic Sciences, University of Nevada Las Vegas, Las Vegas, NV (United States); Advanced Medical Imaging and Genetics (Amigenics), Las Vegas, NV (United States)

    2011-06-15

    The availability of whole brain computed tomography (CT) perfusion has expanded the opportunities for analysing the haemodynamic parameters associated with varied neurological conditions. Examples demonstrating the clinical utility of whole-brain CT perfusion imaging in selected acute and chronic ischaemic arterial neurovascular conditions are presented. Whole-brain CT perfusion enables the detection and focused haemodynamic analyses of acute and chronic arterial conditions in the central nervous system without the limitation of partial anatomical coverage of the brain.

  15. Automated segmentation of three-dimensional MR brain images

    Science.gov (United States)

    Park, Jonggeun; Baek, Byungjun; Ahn, Choong-Il; Ku, Kyo Bum; Jeong, Dong Kyun; Lee, Chulhee

    2006-03-01

    Brain segmentation is a challenging problem due to the complexity of the brain. In this paper, we propose an automated brain segmentation method for 3D magnetic resonance (MR) brain images which are represented as a sequence of 2D brain images. The proposed method consists of three steps: pre-processing, removal of non-brain regions (e.g., the skull, meninges, other organs, etc), and spinal cord restoration. In pre-processing, we perform adaptive thresholding which takes into account variable intensities of MR brain images corresponding to various image acquisition conditions. In segmentation process, we iteratively apply 2D morphological operations and masking for the sequences of 2D sagittal, coronal, and axial planes in order to remove non-brain tissues. Next, final 3D brain regions are obtained by applying OR operation for segmentation results of three planes. Finally we reconstruct the spinal cord truncated during the previous processes. Experiments are performed with fifteen 3D MR brain image sets with 8-bit gray-scale. Experiment results show the proposed algorithm is fast, and provides robust and satisfactory results.

  16. Functional brain imaging of gastrointestinal sensation in health and disease

    Institute of Scientific and Technical Information of China (English)

    Lukas Van Oudenhove; Steven J Coen; Qasim Aziz

    2007-01-01

    It has since long been known, from everyday experience as well as from animal and human studies, that psychological processes-both affective and cognitiveexert an influence on gastrointestinal sensorimotor function. More specifically, a link between psychological factors and visceral hypersensitivity has been suggested,mainly based on research in functional gastrointestinal disorder patients. However, until recently, the exact nature of this putative relationship remained unclear,mainly due to a lack of non-invasive methods to study the (neurobiological) mechanisms underlying this relationship in non-sleeping humans. As functional brain imaging, introduced in visceral sensory neuroscience some 10 years ago, does provide a method for in vivo study of brain-gut interactions, insight into the neurobiological mechanisms underlying visceral sensation in general and the influence of psychological factors more particularly,has rapidly grown. In this article, an overview of brain imaging evidence on gastrointestinal sensation will be given, with special emphasis on the brain mechanisms underlying the interaction between affective & cognitive processes and visceral sensation. First, the reciprocal neural pathways between the brain and the gut (braingut axis) will be briefly outlined, including brain imaging evidence in healthy volunteers. Second, functional brain imaging studies assessing the influence of psychological factors on brain processing of visceral sensation in healthy humans will be discussed in more detail.Finally, brain imaging work investigating differences in brain responses to visceral distension between healthy volunteers and functional gastrointestinal disorder patients will be highlighted.

  17. OUR APPROACH TOWARDS DEVELOPING A SPECIFIC TUMOR-TARGETED MRI CONTRAST AGENT FOR THE BRAIN

    NARCIS (Netherlands)

    GO, KG; BULTE, JWM; DELEY, L; THE, TH; KAMMAN, RL; HULSTAERT, CE; BLAAUW, EH; MA, LD

    1993-01-01

    This review presents various aspects of the technological development, and their assessment in the design of a contrast agent for MRI, tailored to visualise tumours in the brain. First, it was demonstrated that magnetite as a contrast agent exhibited a much stronger relaxivity than gadolinium. The p

  18. Cellular image segmentation using n-agent cooperative game theory

    Science.gov (United States)

    Dimock, Ian B.; Wan, Justin W. L.

    2016-03-01

    Image segmentation is an important problem in computer vision and has significant applications in the segmentation of cellular images. Many different imaging techniques exist and produce a variety of image properties which pose difficulties to image segmentation routines. Bright-field images are particularly challenging because of the non-uniform shape of the cells, the low contrast between cells and background, and imaging artifacts such as halos and broken edges. Classical segmentation techniques often produce poor results on these challenging images. Previous attempts at bright-field imaging are often limited in scope to the images that they segment. In this paper, we introduce a new algorithm for automatically segmenting cellular images. The algorithm incorporates two game theoretic models which allow each pixel to act as an independent agent with the goal of selecting their best labelling strategy. In the non-cooperative model, the pixels choose strategies greedily based only on local information. In the cooperative model, the pixels can form coalitions, which select labelling strategies that benefit the entire group. Combining these two models produces a method which allows the pixels to balance both local and global information when selecting their label. With the addition of k-means and active contour techniques for initialization and post-processing purposes, we achieve a robust segmentation routine. The algorithm is applied to several cell image datasets including bright-field images, fluorescent images and simulated images. Experiments show that the algorithm produces good segmentation results across the variety of datasets which differ in cell density, cell shape, contrast, and noise levels.

  19. Intracranial Hemorrhage Annotation for CT Brain Images

    Directory of Open Access Journals (Sweden)

    Tong Hau Lee

    2011-01-01

    Full Text Available In this paper, we created a decision-making model to detect intracranial hemorrhage and adopted Expectation Maximization(EM segmentation to segment the Computed Tomography (CT images. In this work, basically intracranial hemorrhage is classified into two main types which are intra-axial hemorrhage and extra-axial hemorrhage. In order to ease classification, contrast enhancement is adopted to finetune the contrast of the hemorrhage. After that, k-means is applied to group the potential and suspicious hemorrhagic regions into one cluster. The decision-making process is to identify whether the suspicious regions are hemorrhagic regions or non-regions of interest. After the hemorrhagic detection, the images are segmented into brain matter and cerebrospinal fluid (CSF by using expectation-maximization (EM segmentation. The acquired experimental results are evaluated in terms of recall and precision. The encouraging results have been attained whereby the proposed system has yielded 0.9333 and 0.8880 precision for extra-axial and intra-axial hemorrhagic detection respectively, whereas recall rate obtained is 0.9245 and 0.8043 for extra-axial and intra-axial hemorrhagic detection respectively.

  20. Pharmacological studies of dopamine transporter imaging agent 125/131I-β-CIT

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    To prepare 125/131I-β-CIT (2β-carbomethoxy-3β- (4-iodophenyl)tropane)as an imaging agent for dopamine transporter (DAT), the labeling method from tributylstannyl precursor with peracetic acid has been reported in this article. The radiochemical purity (RCP) of the labeled compound was over 95% determined by HPLC and TLC. The stability, partition coefficients were also determined. The pharmacological studies of the imaging agent were performed in rats, mice, rabbits and normal monkey. The ligand showed preferable uptake in brain (1.9%ID/organ in rats and 4.5%ID/organ in mice at 5 min). The ratios of striatum/cerebellum, hippocampus/cerebellum and cortex/cerebellum were 28.9, 3.97 and 4.75 at 6h in rats, and 8.52, 2.99 and 3.06 at 6h in mice, respectively. In monkey brain imaging the ratios of striatum/frontal cortex (ST/FC) and striatum/occipital cortex (ST/OC) were 5.14 and 5.97 at 4h, respectively. All of above showed the high affinity of the ligand to DAT. The compound was primarily metabolized in liver because the hepatic uptake was much higher than other organs (75.4%ID/organ at 18 h). The half-life of blood elimination was 5 min. The dose received by mice was 2500 times as high as that received by human in the test of undue toxicity, which evaluated the safety of the agent. All the results suggest that β-CIT can be used as a potential DAT imaging agent.

  1. Rhesus monkey brain imaging through intact skull with thermoacoustic tomography.

    Science.gov (United States)

    Xu, Yuan; Wang, Lihong V

    2006-03-01

    Two-dimensional microwave-induced thermoacoustic tomography (TAT) is applied to imaging the Rhesus monkey brain through the intact skull. To reduce the wavefront distortion caused by the skull, only the low-frequency components of the thermoacoustic signals (images. The methods of signal processing and image reconstruction are validated by imaging a lamb kidney. The resolution of the system is found to be 4 mm when we image a 1-month-old monkey head containing inserted needles. We also image the coronal and axial sections of a 7-month-old monkey head. Brain features that are 3 cm deep in the head are imaged clearly. Our results demonstrate that TAT has potential for use in portable, cost-effective imagers for pediatric brains.

  2. Diagnosing Autism Spectrum Disorder through Brain Functional Magnetic Resonance Imaging

    Science.gov (United States)

    2016-03-01

    Diagnosing Autism Spectrum Disorder through Brain Functional Magnetic Resonance Imaging THESIS MARCH 2016 Kyle A. Palko, Second Lieutenant, USAF AFIT...DISORDER THROUGH BRAIN FUNCTIONAL MAGNETIC RESONANCE IMAGING THESIS Presented to the Faculty Department of Operational Sciences Graduate School of...available data includes raw fMRI as well as processed MP RAGE1 images . All data within the ABIDE database was compiled through studies on autism. All

  3. Automated in situ brain imaging for mapping the Drosophila connectome.

    Science.gov (United States)

    Lin, Chi-Wen; Lin, Hsuan-Wen; Chiu, Mei-Tzu; Shih, Yung-Hsin; Wang, Ting-Yuan; Chang, Hsiu-Ming; Chiang, Ann-Shyn

    2015-01-01

    Mapping the connectome, a wiring diagram of the entire brain, requires large-scale imaging of numerous single neurons with diverse morphology. It is a formidable challenge to reassemble these neurons into a virtual brain and correlate their structural networks with neuronal activities, which are measured in different experiments to analyze the informational flow in the brain. Here, we report an in situ brain imaging technique called Fly Head Array Slice Tomography (FHAST), which permits the reconstruction of structural and functional data to generate an integrative connectome in Drosophila. Using FHAST, the head capsules of an array of flies can be opened with a single vibratome sectioning to expose the brains, replacing the painstaking and inconsistent brain dissection process. FHAST can reveal in situ brain neuroanatomy with minimal distortion to neuronal morphology and maintain intact neuronal connections to peripheral sensory organs. Most importantly, it enables the automated 3D imaging of 100 intact fly brains in each experiment. The established head model with in situ brain neuroanatomy allows functional data to be accurately registered and associated with 3D images of single neurons. These integrative data can then be shared, searched, visualized, and analyzed for understanding how brain-wide activities in different neurons within the same circuit function together to control complex behaviors.

  4. Effects of exogenous agents on brain development: stress, abuse and therapeutic compounds.

    Science.gov (United States)

    Archer, Trevor

    2011-10-01

    The range of exogenous agents likely to affect, generally detrimentally, the normal development of the brain and central nervous system defies estimation although the amount of accumulated evidence is enormous. The present review is limited to certain types of chemotherapeutic and "use-and-abuse" compounds and environmental agents, exemplified by anesthetic, antiepileptic, sleep-inducing and anxiolytic compounds, nicotine and alcohol, and stress as well as agents of infection; each of these agents have been investigated quite extensively and have been shown to contribute to the etiopathogenesis of serious neuropsychiatric disorders. To greater or lesser extent, all of the exogenous agents discussed in the present treatise have been investigated for their influence upon neurodevelopmental processes during the period of the brain growth spurt and during other phases uptill adulthood, thereby maintaining the notion of critical phases for the outcome of treatment whether prenatal, postnatal, or adolescent. Several of these agents have contributed to the developmental disruptions underlying structural and functional brain abnormalities that are observed in the symptom and biomarker profiles of the schizophrenia spectrum disorders and the fetal alcohol spectrum disorders. In each case, the effects of the exogenous agents upon the status of the affected brain, within defined parameters and conditions, is generally permanent and irreversible.

  5. Radioisotope scanning of brain, liver, lung and bone with a note on tumour localizing agents

    Science.gov (United States)

    Lavender, J. P.

    1973-01-01

    Radioisotopic scanning of brain, liver, lungs and the skeleton is briefly reviewed with a survey of recent developments of clinical significance. In brain scanning neoplasm detection rates of greater than 90% are claimed. The true figure is probably 70-80%. Autopsy data shows a number of false negatives, particularly with vascular lesions. Attempts to make scanning more specific in differentiating neoplasm from vascular lesions by rapid sequence blood flow studies are reviewed. In liver scanning by means of colloids again high success rate is claimed but small metastases are frequently missed and the false negative scan rate is probably quite high. Lung scanning still has its main place in investigating pulmonary embolic disease. Ventilation studies using Xenon 133 are useful, particularly combined with perfusion studies. The various radiopharmaceuticals for use in bone scanning are reviewed. The appearance of technetium labelled phosphate compounds will probably allow much wider use of total skeletal scanning. Research into tumour localizing agents continues, the most recent and interesting being Gallium citrate and labelled bleomycin. Neither agent is predictable however although Gallium may have a place in Hodgkins disease and bronchogenic neoplasm and both may have a place in the detection of cerebral tumours. ImagesFig. 1Fig. 2Fig. 3p452-bFig. 3bFig. 4Fig. 5Fig. 5bFig. 6Fig. 7Fig. 8Fig. 9Fig. 10Fig. 11Fig. 12Fig. 12c & 12dFig. 13Fig. 13 b,c,dFig. 14Fig. 14bFig. 15Fig. 15bFig. 16Fig. 17Fig. 18 PMID:4602127

  6. Tissue sensitive imaging and tomography without contrast agents for small animals with Timepix based detectors

    Science.gov (United States)

    Trojanova, E.; Schyns, L. E. J. R.; Ludwig, D.; Jakubek, J.; Le Pape, A.; Sefc, L.; Lotte, S.; Sykora, V.; Turecek, D.; Uher, J.; Verhaegen, F.

    2017-01-01

    The tissue type resolving X-ray radiography and tomography can be performed even without contrast agents. The differences between soft tissue types such as kidney, muscles, fat, liver, brain and spleen were measured based on their spectral response. The Timepix based X-ray imaging detector WidePIX2×5 with 300 μm thick silicon sensors was used for most of the measurements presented in this work. These promising results are used for further optimizations of the detector technology and radiographic methods.

  7. In vivo imaging agents: an international market report

    Energy Technology Data Exchange (ETDEWEB)

    1990-03-01

    The purpose of this study is to provide a global perspective of the in vivo imaging agents business to market planning executives who are working for companies that develop, produce and distribute various types of in vivo imaging agents. Others that could find this study useful include investment bankers, regulatory and governmental authorities and purchasers of these products. The study attempts to diligently provide market data by type for important geographic markets - Western Europe, the U.S.A., and Japan. A competitive intelligence section which discusses companies involved in these markets constitutes the last part of this study. These profiles are not intended to extensively evaluate each company's marketing strengths or strategies but to provide a general idea of the market presence and prospects. A combination of primary and secondary research is used for all findings. (author).

  8. Perfluorocarbon Nanoparticles: Evolution of a Multimodality and Multifunctional Imaging Agent

    Directory of Open Access Journals (Sweden)

    Patrick M. Winter

    2014-01-01

    Full Text Available Perfluorocarbon nanoparticles offer a biologically inert, highly stable, and nontoxic platform that can be specifically designed to accomplish a range of molecular imaging and drug delivery functions in vivo. The particle surface can be decorated with targeting ligands to direct the agent to a variety of biomarkers that are associated with diseases such as cancer, cardiovascular disease, obesity, and thrombosis. The surface can also carry a high payload of imaging agents, ranging from paramagnetic metals for MRI, radionuclides for nuclear imaging, iodine for CT, and florescent tags for histology, allowing high sensitivity mapping of cellular receptors that may be expressed at very low levels in the body. In addition to these diagnostic imaging applications, the particles can be engineered to carry highly potent drugs and specifically deposit them into cell populations that display biosignatures of a variety of diseases. The highly flexible and robust nature of this combined molecular imaging and drug delivery vehicle has been exploited in a variety of animal models to demonstrate its potential impact on the care and treatment of patients suffering from some of the most debilitating diseases.

  9. Pattern recognition on brain magnetic resonance imaging in alpha dystroglycanopathies

    Directory of Open Access Journals (Sweden)

    Bindu Parayil

    2010-01-01

    Full Text Available Alpha dystroglycanopathies are heterogeneous group of disorders both phenotypically and genetically. A subgroup of these patients has characteristic brain imaging findings. Four patients with typical imaging findings of alpha dystroglycanopathy are reported. Phenotypic features included: global developmental delay, contractures, hypotonia and oculomotor abnormalities in all. Other manifestations were consanguinity (3, seizures (3, macrocephaly (1, microcephaly (3, retinal changes (2 and hypogenitalism (2. Magnetic resonance imaging (MRI of the brain revealed polymicrogyria, white matter changes, pontine hypoplasia, and subcortical cerebellar cysts in all the patients, ventriculomegaly, callosal abnormalities, and absent septum pellucidum in two and Dandy -Walker variant malformation in three. Magnetic resonace imaging of the first cousin of one the patient had the same characteristic imaging features. Brain imaging findings were almost identical despite heterogeneity in clinical presentation and histopathological features. Pattern recognition of MR imaging features may serve as a clue to the diagnosis of alpha dystroglycanopathy.

  10. Radiolabelled D2 agonists as prolactinoma imaging agents

    Energy Technology Data Exchange (ETDEWEB)

    Otto, C.A.

    1991-12-31

    Research conducted in this terminal year of support centered on three distinct areas: mAChR ligand localization in pancreas and the effect of Ca{sup +2} on localization, continuation of assessment of quaternized and neutral mAChR ligands for possible use as PET myocardial imaging agents, and initiation of a study to determine the relationship of the nAChR receptor to the cellular receptor for measles virus. Several tables and figures illustrating the results are included.

  11. Synthesis of serotonin transporter imaging agent [125I]ADAM

    Institute of Scientific and Technical Information of China (English)

    LU Chun-Xiong; WU Chun-Ying; JIANG Quan-Fu; CHEN Zheng-Ping; ZHANG Tong-Xing; LI Xiao-Ming; WANG Song-Pei

    2005-01-01

    The synthesis of serotonin transporter imaging agent [125I] -2-((2-((dimethylamino)methyl)phenyl)thio)-5-iodophenylamine([125I] ADAM) was reported. The chemical structure of the labeling precursor 5- (tributylstannyl) -2-((2-((dimethylamino)methyl)phenyl)thio)phenylamine and all its intermediates were verified by IR,1HNMR and MS. The .radioiodinated compound was prepared using iododestannylation reaction by hydrogen peroxide. Final radiochemical purity was above 95% determined by TLC.

  12. Parkinson's disease biomarkers program brain imaging repository.

    Science.gov (United States)

    Ofori, Edward; Du, Guangwei; Babcock, Debra; Huang, Xuemei; Vaillancourt, David E

    2016-01-01

    The Parkinson's Disease Biomarkers Program (PDBP) is a multi-site study designed to identify Parkinson's disease (PD) biomarkers that can be used to improve the understanding of PD pathophysiology and to develop tools that provide novel measures to evaluate PD clinical trials. The PDBP consortium comprises numerous individual projects of which two are specifically geared to the development of brain imaging markers for diagnosis, progression, and prognosis of PD or related disorders. All study data from PD patients, atypical Parkinsonian patients, patients with essential tremor, and healthy controls collected from the sites are integrated in the PDBP database and will be publically available. All subjects are asked to submit blood samples, and undergo a battery of clinical evaluations that cover motor, cognitive, and other background information. In addition, a subset of subjects contributed cerebrospinal fluid samples. A restricted access, web-based Data Management Resource facilitates rapid sharing of data and biosamples across the entire PD research community. The PDBP consortium is a useful resource for research and collaboration aimed at the discovery of biomarkers and their use in understanding the pathophysiology of PD.

  13. Appropriate Contrast Enhancement Measures for Brain and Breast Cancer Images

    Directory of Open Access Journals (Sweden)

    Suneet Gupta

    2016-01-01

    Full Text Available Medical imaging systems often produce images that require enhancement, such as improving the image contrast as they are poor in contrast. Therefore, they must be enhanced before they are examined by medical professionals. This is necessary for proper diagnosis and subsequent treatment. We do have various enhancement algorithms which enhance the medical images to different extents. We also have various quantitative metrics or measures which evaluate the quality of an image. This paper suggests the most appropriate measures for two of the medical images, namely, brain cancer images and breast cancer images.

  14. Transcranial functional ultrasound imaging of the brain using microbubble-enhanced ultrasensitive Doppler.

    Science.gov (United States)

    Errico, Claudia; Osmanski, Bruno-Félix; Pezet, Sophie; Couture, Olivier; Lenkei, Zsolt; Tanter, Mickael

    2016-01-01

    Functional ultrasound (fUS) is a novel neuroimaging technique, based on high-sensitivity ultrafast Doppler imaging of cerebral blood volume, capable of measuring brain activation and connectivity in rodents with high spatiotemporal resolution (100μm, 1ms). However, the skull attenuates acoustic waves, so fUS in rats currently requires craniotomy or a thinned-skull window. Here we propose a non-invasive approach by enhancing the fUS signal with a contrast agent, inert gas microbubbles. Plane-wave illumination of the brain at high frame rate (500Hz compounded sequence with three tilted plane waves, PRF=1500Hz with a 128 element 15MHz linear transducer), yields highly-resolved neurovascular maps. We compared fUS imaging performance through the intact skull bone (transcranial fUS) versus a thinned-skull window in the same animal. First, we show that the vascular network of the adult rat brain can be imaged transcranially only after a bolus intravenous injection of microbubbles, which leads to a 9dB gain in the contrast-to-tissue ratio. Next, we demonstrate that functional increase in the blood volume of the primary sensory cortex after targeted electrical-evoked stimulations of the sciatic nerve is observable transcranially in presence of contrast agents, with high reproducibility (Pearson's coefficient ρ=0.7±0.1, p=0.85). Our work demonstrates that the combination of ultrafast Doppler imaging and injection of contrast agent allows non-invasive functional brain imaging through the intact skull bone in rats. These results should ease non-invasive longitudinal studies in rodents and open a promising perspective for the adoption of highly resolved fUS approaches for the adult human brain.

  15. Double-echo perfusion-weighted MR imaging: basic concepts and application in brain tumors for the assessment of tumor blood volume and vascular permeability

    OpenAIRE

    Uematsu, Hidemasa; Maeda, Masayuki

    2006-01-01

    Perfusion-weighted magnetic resonance (MR) imaging using contrast agents plays a key role in characterizing tumors of the brain. We have shown that double-echo perfusion-weighted MR imaging (DEPWI) is potentially useful in assessing brain tumors. Quantitative indices, such as tumor blood volume, are obtained using DEPWI, which allows correction of underestimation of tumor blood volume due to leakage of contrast agents from tumor vessels, in addition to simultaneous acquisition of tumor vessel...

  16. Implementing Tumor Detection and Area Calculation in Mri Image of Human Brain Using Image Processing Techniques

    OpenAIRE

    Sunil L. Bangare; Madhura Patil

    2015-01-01

    This paper is based on the research on Human Brain Tumor which uses the MRI imaging technique to capture the image. In this proposed work Brain Tumor area is calculated to define the Stage or level of seriousness of the tumor. Image Processing techniques are used for the brain tumor area calculation and Neural Network algorithms for the tumor position calculation. Also in the further advancement the classification of the tumor based on few parameters is also expected. Proposed wor...

  17. Mechanism of Chronic Pain in Rodent Brain Imaging

    Science.gov (United States)

    Chang, Pei-Ching

    Chronic pain is a significant health problem that greatly impacts the quality of life of individuals and imparts high costs to society. Despite intense research effort in understanding of the mechanism of pain, chronic pain remains a clinical problem that has few effective therapies. The advent of human brain imaging research in recent years has changed the way that chronic pain is viewed. To further extend the use of human brain imaging techniques for better therapies, the adoption of imaging technique onto the animal pain models is essential, in which underlying brain mechanisms can be systematically studied using various combination of imaging and invasive techniques. The general goal of this thesis is to addresses how brain develops and maintains chronic pain in an animal model using fMRI. We demonstrate that nucleus accumbens, the central component of mesolimbic circuitry, is essential in development of chronic pain. To advance our imaging technique, we develop an innovative methodology to carry out fMRI in awake, conscious rat. Using this cutting-edge technique, we show that allodynia is assoicated with shift brain response toward neural circuits associated nucleus accumbens and prefrontal cortex that regulate affective and cognitive component of pain. Taken together, this thesis provides a deeper understanding of how brain mediates pain. It builds on the existing body of knowledge through maximizing the depth of insight into brain imaging of chronic pain.

  18. Functional brain imaging studies on specificity of meridian and acupoints

    Institute of Scientific and Technical Information of China (English)

    Xuezhi Li; Xuguang Liu; Fanrong Liang

    2008-01-01

    At present,the specificity of meridians and acupoints has been studied using functional brain imaging techniques from many standpoints.including meridians,acupoints,and sham acupoints,as well as different meridians and acupoints,coordination of acupoints,and factors influencing meridian and acupoint specificity.Preliminary experimental data have demonstrated that acupuncture at meridians and acupoints is specific with regard to brain neural information.However,research findings are contradictory,which may be related to brain functional complexity,resolution of functional brain imaging techniques,and experimental design.Future studies should further improve study method,and should strictly control experimental conditions to better analyze experimental data and acquire more beneficial data.Because of its many advantages.the functional brain imaging technique is a promising method for studying meridian and acupoint specificity.

  19. Brain imaging of pain: state of the art.

    Science.gov (United States)

    Morton, Debbie L; Sandhu, Javin S; Jones, Anthony Kp

    2016-01-01

    Pain is a complex sensory and emotional experience that is heavily influenced by prior experience and expectations of pain. Before the development of noninvasive human brain imaging, our grasp of the brain's role in pain processing was limited to data from postmortem studies, direct recording of brain activity, patient experience and stimulation during neurosurgical procedures, and animal models of pain. Advances made in neuroimaging have bridged the gap between brain activity and the subjective experience of pain and allowed us to better understand the changes in the brain that are associated with both acute and chronic pain. Additionally, cognitive influences on pain such as attention, anticipation, and fear can now be directly observed, allowing for the interpretation of the neural basis of the psychological modulation of pain. The use of functional brain imaging to measure changes in endogenous neurochemistry has increased our understanding of how states of increased resilience and vulnerability to pain are maintained.

  20. MR fluid-attenuated inversion recovery imaging as routine brain T2-weighted imaging

    Energy Technology Data Exchange (ETDEWEB)

    Arakia, Yutaka; Ashikaga, Ryuichiro; Fujii, Koichi; Nishimura, Yasumasa; Ueda, Jun; Fujita, Norihiko

    1999-11-01

    We tried to investigate if magnetic resonance (MR) fluid-attenuated inversion recovery (FLAIR) imaging can be used as a routine brain screening examination instead of spin-echo T2-weighted imaging. Three hundred and ninety-four patients with clinically suspected brain diseases were randomly selected and examined with both brain MR FLAIR and T2-weighted imaging on the axial plane. These two imaging techniques were evaluated by two neuroradiologists as to which imaging was better for routine brain T2-weighted imaging. In 123 of 394 cases (31%), FLAIR imaging was superior to spin-echo T2-weighted imaging. Especially in cases with inflammatory diseases, traumatic diseases and demyelinating diseases, FLAIR imaging was particularly useful. Small lesions bordering cerebrospinal fluid (CSF) are often detected only by FLAIR imaging. In 259 cases (66%), including 147 normal cases (37%), they were equally evaluated. Only in 12 cases (3%) was conventional T2-weighted imaging superior to FLAIR imaging. Cerebrovascular lesions like cerebral aneurysm and Moyamoya disease could not be detected on FLAIR images because these structures were obscured by a low signal from the CSF. Also, because old infarctions tend to appear as low signal intensity on FLAIR images, the condition was sometimes hard to detect. Finally, FLAIR imaging could be used as routine brain T2-weighted imaging instead of conventional spin-echo T2-weighted imaging if these vascular lesions were watched.

  1. Primary study of a novel Tc-tricarbonyl cocaine analogue as the potential DAT imaging agent

    Institute of Scientific and Technical Information of China (English)

    ZHANG Xiaobo; ZHU Lin; DING Shaoke; LIU Boli

    2005-01-01

    The convenient preparation of organometallic precursor fac-[99mTc(CO)3 (H2O)3]+ opens a new route to design new radiopharmaceuticals. Based on this precursor, a new cocaine analogue, Tropyn, is designed and synthesized, and "2+1" mixed-ligands approach is used to prepare a neutral complex [99mTc(CO)3(Tropyn)I]. Biodistribution in mice and rats proves that it has sufficient brain uptake. Rat regional brain biodistribution indicates that the complex is highly concentrated in the striatum (ST) with rapid clearance in the cortex (CT) and hippocampus (HP), which make it valuable for further investigation as the potential Second-Generation DAT imaging agent.

  2. NMR imaging of cell phone radiation absorption in brain tissue

    OpenAIRE

    Gultekin, David H.; Moeller, Lothar

    2012-01-01

    A method is described for measuring absorbed electromagnetic energy radiated from cell phone antennae into ex vivo brain tissue. NMR images the 3D thermal dynamics inside ex vivo bovine brain tissue and equivalent gel under exposure to power and irradiation time-varying radio frequency (RF) fields. The absorbed RF energy in brain tissue converts into Joule heat and affects the nuclear magnetic shielding and the Larmor precession. The resultant temperature increase is measured by the resonance...

  3. A paramagnetic CEST agent for imaging glucose by MRI.

    Science.gov (United States)

    Zhang, Shanrong; Trokowski, Robert; Sherry, A Dean

    2003-12-17

    The europium(III) complex of a DOTA-tetraamide ligand (DOTA = 1,4,7,10-tetraazacyclododecane-N,N',N' ',N' ''-tetraacetic acids) containing two phenyl boronate pendent arms binds glucose reversibly with an association constant of 383 M-1 at pH 7. Glucose binding results in slowing of water exchange between a single Eu(III)-bound water molecule and bulk water, and this can be imaged by MRI using chemical exchange saturation transfer (CEST) imaging sequence. This metabolite-responsive paramagnetic CEST agent responds to changes in glucose over the physiologically important range (0-20 mM), and thus it offers the possibility of high-sensitivity MR imaging glucose in tissues using bulk water protons as antenna.

  4. Moxifloxacin: Clinically compatible contrast agent for multiphoton imaging

    Science.gov (United States)

    Wang, Taejun; Jang, Won Hyuk; Lee, Seunghun; Yoon, Calvin J.; Lee, Jun Ho; Kim, Bumju; Hwang, Sekyu; Hong, Chun-Pyo; Yoon, Yeoreum; Lee, Gilgu; Le, Viet-Hoan; Bok, Seoyeon; Ahn, G.-One; Lee, Jaewook; Gho, Yong Song; Chung, Euiheon; Kim, Sungjee; Jang, Myoung Ho; Myung, Seung-Jae; Kim, Myoung Joon; So, Peter T. C.; Kim, Ki Hean

    2016-06-01

    Multiphoton microscopy (MPM) is a nonlinear fluorescence microscopic technique widely used for cellular imaging of thick tissues and live animals in biological studies. However, MPM application to human tissues is limited by weak endogenous fluorescence in tissue and cytotoxicity of exogenous probes. Herein, we describe the applications of moxifloxacin, an FDA-approved antibiotic, as a cell-labeling agent for MPM. Moxifloxacin has bright intrinsic multiphoton fluorescence, good tissue penetration and high intracellular concentration. MPM with moxifloxacin was demonstrated in various cell lines, and animal tissues of cornea, skin, small intestine and bladder. Clinical application is promising since imaging based on moxifloxacin labeling could be 10 times faster than imaging based on endogenous fluorescence.

  5. Skull-stripping for Tumor-bearing Brain Images

    CERN Document Server

    Bauer, Stefan; Reyes, Mauricio

    2012-01-01

    Skull-stripping separates the skull region of the head from the soft brain tissues. In many cases of brain image analysis, this is an essential preprocessing step in order to improve the final result. This is true for both registration and segmentation tasks. In fact, skull-stripping of magnetic resonance images (MRI) is a well-studied problem with numerous publications in recent years. Many different algorithms have been proposed, a summary and comparison of which can be found in [Fennema-Notestine, 2006]. Despite the abundance of approaches, we discovered that the algorithms which had been suggested so far, perform poorly when dealing with tumor-bearing brain images. This is mostly due to additional difficulties in separating the brain from the skull in this case, especially when the lesion is located very close to the skull border. Additionally, images acquired according to standard clinical protocols, often exhibit anisotropic resolution and only partial coverage, which further complicates the task. There...

  6. Imaging of brain tumors with histological correlations. 2. ed.

    Energy Technology Data Exchange (ETDEWEB)

    Drevelegas, Antonios (ed.)

    2011-07-01

    This volume provides a deeper understanding of the diagnosis of brain tumors by correlating radiographic imaging features with the underlying pathological abnormalities. All modern imaging modalities are used to complete a diagnostic overview of brain tumors with emphasis on recent advances in diagnostic neuroradiology. High-quality illustrations depicting common and uncommon imaging characteristics of a wide range of brain tumors are presented and analysed, drawing attention to the ways in which these characteristics reflect different aspects of pathology. Important theoretical considerations are also discussed. Since the first edition, chapters have been revised and updated and new material has been added, including detailed information on the clinical application of functional MRI and diffusion tensor imaging. Radiologists and other clinicians interested in the current diagnostic approach to brain tumors will find this book to be an invaluable and enlightening clinical tool. (orig.)

  7. Blood-Brain Barrier Imaging in Human Neuropathologies

    Science.gov (United States)

    Veksler, Ronel; Shelef, Ilan; Friedman, Alon

    2014-01-01

    The blood–brain barrier (BBB) is essential for normal function of the brain, and its role in many brain pathologies has been the focus of numerous studies during the last decades. Dysfunction of the BBB is not only being shown in numerous brain diseases, but animal studies have indicated that it plays a direct key role in the genesis of neurovascular dysfunction and associated neurodegeneration. As such evidence accumulates, the need for robust and clinically applicable methods for minimally invasive assessment of BBB integrity is becoming urgent. This review provides an introduction to BBB imaging methods in the clinical scenario. First, imaging modalities are reviewed, with a focus on dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI). We then proceed to review image analysis methods, including quantitative and semi-quantitative methods. The advantages and limitations of each approach are discussed, and future directions and questions are highlighted. PMID:25453223

  8. Automated morphometry of transgenic mouse brains in MR images

    NARCIS (Netherlands)

    Scheenstra, Alize Elske Hiltje

    2011-01-01

    Quantitative and local morphometry of mouse brain MRI is a relatively new field of research, where automated methods can be exploited to rapidly provide accurate and repeatable results. In this thesis we reviewed several existing methods and applications of quantitative morphometry to brain MR image

  9. PET/SPECT imaging : From carotid vulnerability to brain viability

    NARCIS (Netherlands)

    Meerwaldt, Robbert; Slart, Riemer H. J. A.; van Dam, Gooitzen M.; Luijckx, Gert-Jan; Tio, Rene A.; Zeebregts, Clark J.

    2010-01-01

    Background: Current key issues in ischemic stroke are related to carotid plaque vulnerability, brain viability, and timing of intervention. The treatment of ischemic stroke has evolved into urgent active interventions, as 'time is brain'. Functional imaging such as positron emission tomography (PET)

  10. Structural brain imaging in diabetes : A methodological perspective

    NARCIS (Netherlands)

    Jongen, Cynthia; Biessels, Geert Jan

    2008-01-01

    Brain imaging provides information on brain anatomy and function and progression of cerebral abnormalities can be monitored. This may provide insight into the aetiology of diabetes related cerebral disorders. This paper focuses on the methods for the assessment of white matter hyperintensities and b

  11. STEREOLOGICAL EVALUATION OF BRAIN MAGNETIC RESONANCE IMAGES OF SCHIZOPHRENIC PATIENTS

    Directory of Open Access Journals (Sweden)

    Amani Abdelrazag Elfaki

    2013-11-01

    Full Text Available Advances in neuroimaging have enabled studies of specific neuroanatomical abnormalities with relevance to schizophrenia. This study quantified structural alterations on brain magnetic resonance (MR images of patients with schizophrenia. MR brain imaging was done on 88 control and 57 schizophrenic subjects and Dicom images were analyzed with ImageJ software. The brain volume was estimated with the planimetric stereological technique. The volume fraction of brain structures was also estimated. The results showed that, the mean volume of right, left, and total hemispheres in controls were 551, 550, and 1101 cm³, respectively. The mean volumes of right, left, and total hemispheres in schizophrenics were 513, 512, and 1026 cm³, respectively. The schizophrenics’ brains were smaller than the controls (p < 0.05. The mean volume of total white matter of controls (516 cm³ was bigger than the schizophrenics’ volume (451 cm³, (p < 0.05. The volume fraction of total white matter was also lower in schizophrenics (p < 0.05. Volume fraction of the lateral ventricles was higher in schizophrenics (p < 0.05. According to the findings, the volumes of schizophrenics’ brain were smaller than the controls and the volume fractional changes in schizophrenics showed sex dependent differences. We conclude that stereological analysis of MR brain images is useful for quantifying schizophrenia related structural changes.

  12. DATA SYNTHESIS AND METHOD EVALUATION FOR BRAIN IMAGING GENETICS

    OpenAIRE

    Sheng, Jinhua; Kim, Sungeun; Yan, Jingwen; Moore, Jason; Saykin, Andrew; Shen, Li

    2014-01-01

    Brain imaging genetics is an emergent research field where the association between genetic variations such as single nucleotide polymorphisms (SNPs) and neuroimaging quantitative traits (QTs) is evaluated. Sparse canonical correlation analysis (SCCA) is a bi-multivariate analysis method that has the potential to reveal complex multi-SNP-multi-QT associations. We present initial efforts on evaluating a few SCCA methods for brain imaging genetics. This includes a data synthesis method to create...

  13. Unsupervised Neural Techniques Applied to MR Brain Image Segmentation

    Directory of Open Access Journals (Sweden)

    A. Ortiz

    2012-01-01

    Full Text Available The primary goal of brain image segmentation is to partition a given brain image into different regions representing anatomical structures. Magnetic resonance image (MRI segmentation is especially interesting, since accurate segmentation in white matter, grey matter and cerebrospinal fluid provides a way to identify many brain disorders such as dementia, schizophrenia or Alzheimer’s disease (AD. Then, image segmentation results in a very interesting tool for neuroanatomical analyses. In this paper we show three alternatives to MR brain image segmentation algorithms, with the Self-Organizing Map (SOM as the core of the algorithms. The procedures devised do not use any a priori knowledge about voxel class assignment, and results in fully-unsupervised methods for MRI segmentation, making it possible to automatically discover different tissue classes. Our algorithm has been tested using the images from the Internet Brain Image Repository (IBSR outperforming existing methods, providing values for the average overlap metric of 0.7 for the white and grey matter and 0.45 for the cerebrospinal fluid. Furthermore, it also provides good results for high-resolution MR images provided by the Nuclear Medicine Service of the “Virgen de las Nieves” Hospital (Granada, Spain.

  14. Do brain image databanks support understanding of normal ageing brain structure? A systematic review

    Energy Technology Data Exchange (ETDEWEB)

    Dickie, David Alexander; Job, Dominic E.; Wardlaw, Joanna M. [University of Edinburgh, Division of Clinical Neurosciences, Western General Hospital, Brain Research Imaging Centre (BRIC), Edinburgh (United Kingdom); Scottish Imaging Network, A Platform for Scientific Excellence (SINAPSE), Edinburgh (United Kingdom); Poole, Ian [Toshiba Medical Visualisation Systems Europe, Ltd., Edinburgh (United Kingdom); Ahearn, Trevor S.; Staff, Roger T.; Murray, Alison D. [University of Aberdeen, Aberdeen Biomedical Imaging Centre, Aberdeen (United Kingdom); Scottish Imaging Network, A Platform for Scientific Excellence (SINAPSE), Edinburgh (United Kingdom)

    2012-07-15

    To document accessible magnetic resonance (MR) brain images, metadata and statistical results from normal older subjects that may be used to improve diagnoses of dementia. We systematically reviewed published brain image databanks (print literature and Internet) concerned with normal ageing brain structure. From nine eligible databanks, there appeared to be 944 normal subjects aged {>=}60 years. However, many subjects were in more than one databank and not all were fully representative of normal ageing clinical characteristics. Therefore, there were approximately 343 subjects aged {>=}60 years with metadata representative of normal ageing, but only 98 subjects were openly accessible. No databank had the range of MR image sequences, e.g. T2*, fluid-attenuated inversion recovery (FLAIR), required to effectively characterise the features of brain ageing. No databank supported random subject retrieval; therefore, manual selection bias and errors may occur in studies that use these subjects as controls. Finally, no databank stored results from statistical analyses of its brain image and metadata that may be validated with analyses of further data. Brain image databanks require open access, more subjects, metadata, MR image sequences, searchability and statistical results to improve understanding of normal ageing brain structure and diagnoses of dementia. (orig.)

  15. Reactivation of Brain Acetylcholinesterase by Monoisonitrosoacetone Increases the Therapeutic Efficacy Against Nerve Agents in Guinea Pigs

    Science.gov (United States)

    2010-01-01

    Biological Interactions 187 (2010) 318–324 Table 1 ChE reactivation by oxime treatments in brain regions, peripheral tissues and blood components following...the significant ChE reactivation by oxime treatments in brain regions, peripheral tissues and blood components following exposure to GB, GF, and VX.a...regions, peripheral tis- ues, or blood components , when an oxime treatment significantly eactivated nerve agent-inhibited ChE. For example, if an

  16. The Potential of Using Brain Images for Authentication

    Directory of Open Access Journals (Sweden)

    Fanglin Chen

    2014-01-01

    Full Text Available Biometric recognition (also known as biometrics refers to the automated recognition of individuals based on their biological or behavioral traits. Examples of biometric traits include fingerprint, palmprint, iris, and face. The brain is the most important and complex organ in the human body. Can it be used as a biometric trait? In this study, we analyze the uniqueness of the brain and try to use the brain for identity authentication. The proposed brain-based verification system operates in two stages: gray matter extraction and gray matter matching. A modified brain segmentation algorithm is implemented for extracting gray matter from an input brain image. Then, an alignment-based matching algorithm is developed for brain matching. Experimental results on two data sets show that the proposed brain recognition system meets the high accuracy requirement of identity authentication. Though currently the acquisition of the brain is still time consuming and expensive, brain images are highly unique and have the potential possibility for authentication in view of pattern recognition.

  17. The potential of using brain images for authentication.

    Science.gov (United States)

    Chen, Fanglin; Zhou, Zongtan; Shen, Hui; Hu, Dewen

    2014-01-01

    Biometric recognition (also known as biometrics) refers to the automated recognition of individuals based on their biological or behavioral traits. Examples of biometric traits include fingerprint, palmprint, iris, and face. The brain is the most important and complex organ in the human body. Can it be used as a biometric trait? In this study, we analyze the uniqueness of the brain and try to use the brain for identity authentication. The proposed brain-based verification system operates in two stages: gray matter extraction and gray matter matching. A modified brain segmentation algorithm is implemented for extracting gray matter from an input brain image. Then, an alignment-based matching algorithm is developed for brain matching. Experimental results on two data sets show that the proposed brain recognition system meets the high accuracy requirement of identity authentication. Though currently the acquisition of the brain is still time consuming and expensive, brain images are highly unique and have the potential possibility for authentication in view of pattern recognition.

  18. Consistent Reconstruction of Cortical Surfaces from Longitudinal Brain MR Images

    OpenAIRE

    Li, Gang; Nie, Jingxin; Shen, Dinggang

    2011-01-01

    Accurate and consistent reconstruction of cortical surfaces from longitudinal human brain MR images is of great importance in studying subtle morphological changes of the cerebral cortex. This paper presents a new deformable surface method for consistent and accurate reconstruction of inner, central and outer cortical surfaces from longitudinal MR images. Specifically, the cortical surfaces of the group-mean image of all aligned longitudinal images of the same subject are first reconstructed ...

  19. Evaluation of 7 {alpha}-O-IADPN as a new potential SPECT opioid receptor imaging agent

    Energy Technology Data Exchange (ETDEWEB)

    Wang, R.F.; Mao, S.Y. [Fujian Medical College, Fuzhou (China). Dept. of Nuclear Medicine; Tafani, J.A.M.; Coulais, Y.; Guiraud, R. [Hospital Purpan, Toulouse (France). Service Central de medicine Nucleaire; Zajac, J.M. [LPTF-CNRS, Toulouse (France)

    1998-03-01

    Full text: A new iodinated diprenorphine antagonist analogue, [{sup 123}I]7 {alpha}.-O-IADPN, [E] - 17-(cyclopropylmethyl) -4,5 (x-epoxy- 18,19-dihydro-3-hydroxy-6-methoxy-7 {alpha}-[1-(3-iodoallyl)oxy-1-methylethyl]-6,14-endo-ethenomorphinan for in vivo and in vitro studies as a potential central nervous system (CNS) opioid receptor imaging agent was developed. In vivo biodistribution and metabolism of 7 {alpha}-O-lADPN in rat demonstrated that 0.16% of the iodinated compound was presented in mouse brain with a degradation-resistant at the first 60 min, and that 36% of the total cerebral radioactivity and 63% of its specific binding to opioid receptors were observed 20 min after i.v. injection. The cerebral radioactivity in mouse brain concentrated in the basal ganglion and cortex, and displayed a remarkably high target-to-non-target ratio (cortex/cerebellum = 60 min post-injection). The in vitro binding studies showed that [{sup 123}I]7 {alpha}-O-IADPN binds non selectively to multiple opioid receptors {mu} = 8 K) with a very high affinity (Ki = 0.4 + 0.2 nM). Ex vivo autoradiography results in mouse further confirmed the high uptake and retention of this agent in basal ganglion region and cortex. The planar imaging of monkey brains after i.v. injection of [{sup 123}I]7 {alpha}-O-IADPN clearly displayed that multiple opioid receptors can be visualized. With the excellent in vitro affinity and in vivo stability to deiodination and high target-to-nontarget ratio, [{sup 123}I]7 {alpha}- O-IADPN appears to be useful as a CNS opioid receptor imaging probe for SPECT in primate and non-primate.

  20. The preclinical pharmacological study of dopamine transporter imaging agent 18F-FP-β-CIT

    Institute of Scientific and Technical Information of China (English)

    LI Xiaomin; CHEN Zhengping; WANG Songpei; TANG Jie; LIN Yansong; ZHU Zhaohui; FANG Ping

    2007-01-01

    The paper is to study pharmacologic characteristics of 18F-FP-β-CIT (18F-N-(3-fluoropropyl)-2β- carbomethoxy-3β- (4-iodophenyl)nortropane) as an imaging agent for dopamine transporter. The radiochemical purity of 18F-FP-β-CIT in aqueous solution was over 95% after standing at room temperature for 4h. Biodistribution displayed rapid uptake in rat brain (1.375 %ID/organ at 5min and 0.100 %ID/organ at 180 min) and the striatal uptake was 1.444,0.731, 0.397, 0.230 and 0.146 %ID/g at 5, 30, 60, 120 and 180 min, respectively. The values of striatum/cerebellum,striatum/frontal cortex and striatum / hippocampus in rat's brain at 30 min were 3.38, 2.17 and 2.40 respectively. The uptake in striatum can be blocked by β-CFT, suggesting that 18F-FP-β-CIT binds to DAT peculiarly. The compound was rapidly cleared from monkey's blood. The striatal uptake was bilaterally decreased in the left-sided lesioned PD rats, compared with normal control. Brain PET imaging studies in normal monkey showed that 18F-FP-β-CIT was concentrated in striatum. The test of undue toxicity showed that the dose received by mice was 1250 times as by human, which indicates that 18F-FP-β-CIT is very safe. So 18F-FP-β-CIT is a promising PET imaging agent for DAT with safety and validity.

  1. Atypical pyogenic brain abscess evaluation by diffusion-weighted imaging: diagnosis with multimodality MR imaging.

    Science.gov (United States)

    Ozbayrak, Mustafa; Ulus, Ozden Sila; Berkman, Mehmet Zafer; Kocagoz, Sesin; Karaarslan, Ercan

    2015-10-01

    Whether a brain abscess is apparent by imaging depends on the stage of the abscess at the time of imaging, as well as the etiology of the infection. Because conventional magnetic resonance imaging (MRI) is limited in its ability to distinguish brain abscesses from necrotic tumors, advanced techniques are required. The management of these two disease entities differs and can potentially affect the clinical outcome. We report a case having atypical imaging features of a pyogenic brain abscess on advanced MRI, in particular, on diffusion-weighted and perfusion imaging, in a patient with osteosarcoma undergoing chemotherapy.

  2. Salicylic acid analogues as chemical exchange saturation transfer MRI contrast agents for the assessment of brain perfusion territory and blood-brain barrier opening after intra-arterial infusion.

    Science.gov (United States)

    Song, Xiaolei; Walczak, Piotr; He, Xiaowei; Yang, Xing; Pearl, Monica; Bulte, Jeff Wm; Pomper, Martin G; McMahon, Michael T; Janowski, Mirosław

    2016-07-01

    The blood-brain barrier (BBB) is a major obstacle for drug delivery to the brain. Predicted, focal opening of the BBB through intra-arterial infusion of hyperosmolar mannitol is feasible, but there is a need to facilitate imaging techniques (e.g. MRI) to guide interventional procedures and assess the outcomes. Here, we show that salicylic acid analogues (SAA) can depict the brain territory supplied by the catheter and detect the BBB opening, through chemical exchange saturation transfer (CEST) MRI. Hyperosmolar SAA solutions themselves are also capable of opening the BBB, and, when multiple SAA agents were co-injected, their locoregional perfusion could be differentiated.

  3. Computed tomographic imaging of the brain of normal neonatal foals

    Directory of Open Access Journals (Sweden)

    L Cabrera

    2015-01-01

    Full Text Available The aim of this study was to provide a more complete description of normal cross-sectional anatomy of the neonatal brain of the foal and associated structures by computed tomography (CT and gross anatomical sections. Using a fourth-generation CT scanner, 2-mm contiguous transverse images were acquired from two neonatal 5-days-old Quarter horse foals. After the study the animals were euthanised for reasons unrelated to head pathology. To assist in the accurate identification of brain and associated structures, transverse CT images were obtained and compared with the corresponding frozen cross-sections of the head. CT images matched well with their corresponding transverse gross sections and provided good differentiation between the bones and the soft tissues of the head. These CT images are intended to be a useful initial anatomic reference in the interpretation for clinical CT imaging studies of the brain and associated structures in live neonatal foals.

  4. In vivo calcium imaging of the aging and diseased brain

    Energy Technology Data Exchange (ETDEWEB)

    Eichhoff, Gerhard; Busche, Marc A.; Garaschuk, Olga [Technical University of Munich, Institute of Neuroscience, Munich (Germany)

    2008-03-15

    Over the last decade, in vivo calcium imaging became a powerful tool for studying brain function. With the use of two-photon microscopy and modern labelling techniques, it allows functional studies of individual living cells, their processes and their interactions within neuronal networks. In vivo calcium imaging is even more important for studying the aged brain, which is hard to investigate in situ due to the fragility of neuronal tissue. In this article, we give a brief overview of the techniques applicable to image aged rodent brain at cellular resolution. We use multicolor imaging to visualize specific cell types (neurons, astrocytes, microglia) as well as the autofluorescence of the ''aging pigment'' lipofuscin. Further, we illustrate an approach for simultaneous imaging of cortical cells and senile plaques in mouse models of Alzheimer's disease. (orig.)

  5. Multimodal imaging enables early detection and characterization of changes in tumor permeability of brain metastases.

    Science.gov (United States)

    Thorsen, Frits; Fite, Brett; Mahakian, Lisa M; Seo, Jai W; Qin, Shengping; Harrison, Victoria; Johnson, Sarah; Ingham, Elizabeth; Caskey, Charles; Sundstrøm, Terje; Meade, Thomas J; Harter, Patrick N; Skaftnesmo, Kai Ove; Ferrara, Katherine W

    2013-12-28

    Our goal was to develop strategies to quantify the accumulation of model therapeutics in small brain metastases using multimodal imaging, in order to enhance the potential for successful treatment. Human melanoma cells were injected into the left cardiac ventricle of immunodeficient mice. Bioluminescent, MR and PET imaging were applied to evaluate the limits of detection and potential for contrast agent extravasation in small brain metastases. A pharmacokinetic model was applied to estimate vascular permeability. Bioluminescent imaging after injecting d-luciferin (molecular weight (MW) 320 D) suggested that tumor cell extravasation had already occurred at week 1, which was confirmed by histology. 7T T1w MRI at week 4 was able to detect non-leaky 100 μm sized lesions and leaky tumors with diameters down to 200 μm after contrast injection at week 5. PET imaging showed that (18)F-FLT (MW 244 Da) accumulated in the brain at week 4. Gadolinium-based MRI tracers (MW 559 Da and 2.066 kDa) extravasated after 5 weeks (tumor diameter 600 μm), and the lower MW agent cleared more rapidly from the tumor (mean apparent permeabilities 2.27 × 10(-5)cm/s versus 1.12 × 10(-5)cm/s). PET imaging further demonstrated tumor permeability to (64)Cu-BSA (MW 65.55 kDa) at week 6 (tumor diameter 700 μm). In conclusion, high field T1w MRI without contrast may improve the detection limit of small brain metastases, allowing for earlier diagnosis of patients, although the smallest lesions detected with T1w MRI were permeable only to d-luciferin and the amphipathic small molecule (18)F-FLT. Different-sized MR and PET contrast agents demonstrated the gradual increase in leakiness of the blood tumor barrier during metastatic progression, which could guide clinicians in choosing tailored treatment strategies.

  6. The use of contrast agent for imaging biological samples

    Energy Technology Data Exchange (ETDEWEB)

    Dammer, J; Sopko, V; Jakubek, J [Institute of Experimental and Applied Physics, Czech Technical University in Prague, Horska 3a/22, CZ 12800 Prague 2 (Czech Republic); Weyda, F, E-mail: jiri.dammer@utef.cvut.cz [Biological center of the Academy of Sciences of the Czech Republic, Institute of Entomology, Branisovska 31, CZ-37005 Ceske Budejovice (Czech Republic)

    2011-01-15

    The technique of X-ray transmission imaging has been available for over a century and is still among the fastest and easiest approaches to the studies of internal structure of biological samples. Recent advances in semiconductor technology have led to the development of new types of X-ray detectors with direct conversion of interacting X-ray photon to an electric signal. Semiconductor pixel detectors seem to be specially promising; compared to the film technique, they provide single-quantum and real-time digital information about the objects being studied. We describe the recently developed radiographic apparatus, equipped with Medipix2 semiconductor pixel detector. The detector is used as an imager that counts individual photons of ionizing radiation, emitted by an X-ray tube (micro- or nano-focus FeinFocus). Thanks to the wide dynamic range of the Medipix2 detector and its high spatial resolution better than 1{mu}m, the setup is particularly suitable for radiographic imaging of small biological samples, including in-vivo observations with contrast agent (Optiray). Along with the description of the apparatus we provide examples of the use iodine contrast agent as a tracer in various insects as model organisms. The motivation of our work is to develop our imaging techniques as non-destructive and non-invasive. Microradiographic imaging helps detect organisms living in a not visible environment, visualize the internal biological processes and also to resolve the details of their body (morphology). Tiny live insects are an ideal object for our studies.

  7. Three-dimensional microtomographic imaging of human brain cortex

    CERN Document Server

    Mizutania, Ryuta; Uesugi, Kentaro; Ohyama, Masami; Takekoshi, Susumu; Osamura, R Yoshiyuki; Suzuki, Yoshio

    2016-01-01

    This paper describes an x-ray microtomographic technique for imaging the three-dimensional structure of the human cerebral cortex. Neurons in the brain constitute a neural circuit as a three-dimensional network. The brain tissue is composed of light elements that give little contrast in a hard x-ray transmission image. The contrast was enhanced by staining neural cells with metal compounds. The obtained structure revealed the microarchitecture of the gray and white matter regions of the frontal cortex, which is responsible for the higher brain functions.

  8. Numerical Simulations of MREIT Conductivity Imaging for Brain Tumor Detection

    Directory of Open Access Journals (Sweden)

    Zi Jun Meng

    2013-01-01

    Full Text Available Magnetic resonance electrical impedance tomography (MREIT is a new modality capable of imaging the electrical properties of human body using MRI phase information in conjunction with external current injection. Recent in vivo animal and human MREIT studies have revealed unique conductivity contrasts related to different physiological and pathological conditions of tissues or organs. When performing in vivo brain imaging, small imaging currents must be injected so as not to stimulate peripheral nerves in the skin, while delivery of imaging currents to the brain is relatively small due to the skull’s low conductivity. As a result, injected imaging currents may induce small phase signals and the overall low phase SNR in brain tissues. In this study, we present numerical simulation results of the use of head MREIT for brain tumor detection. We used a realistic three-dimensional head model to compute signal levels produced as a consequence of a predicted doubling of conductivity occurring within simulated tumorous brain tissues. We determined the feasibility of measuring these changes in a time acceptable to human subjects by adding realistic noise levels measured from a candidate 3 T system. We also reconstructed conductivity contrast images, showing that such conductivity differences can be both detected and imaged.

  9. Numerical simulations of MREIT conductivity imaging for brain tumor detection.

    Science.gov (United States)

    Meng, Zi Jun; Sajib, Saurav Z K; Chauhan, Munish; Sadleir, Rosalind J; Kim, Hyung Joong; Kwon, Oh In; Woo, Eung Je

    2013-01-01

    Magnetic resonance electrical impedance tomography (MREIT) is a new modality capable of imaging the electrical properties of human body using MRI phase information in conjunction with external current injection. Recent in vivo animal and human MREIT studies have revealed unique conductivity contrasts related to different physiological and pathological conditions of tissues or organs. When performing in vivo brain imaging, small imaging currents must be injected so as not to stimulate peripheral nerves in the skin, while delivery of imaging currents to the brain is relatively small due to the skull's low conductivity. As a result, injected imaging currents may induce small phase signals and the overall low phase SNR in brain tissues. In this study, we present numerical simulation results of the use of head MREIT for brain tumor detection. We used a realistic three-dimensional head model to compute signal levels produced as a consequence of a predicted doubling of conductivity occurring within simulated tumorous brain tissues. We determined the feasibility of measuring these changes in a time acceptable to human subjects by adding realistic noise levels measured from a candidate 3 T system. We also reconstructed conductivity contrast images, showing that such conductivity differences can be both detected and imaged.

  10. Targeted Multifunctional Nanoparticles cure and image Brain Tumors: Selective MRI Contrast Enhancement and Photodynamic Therapy

    Science.gov (United States)

    Kopelman, Raoul

    2008-03-01

    Aimed at targeted therapy and imaging of brain tumors, our approach uses targeted, multi-functional nano-particles (NP). A typical nano-particle contains a biologically inert, non-toxic matrix, biodegradable and bio-eliminable over a long time period. It also contains active components, such as fluorescent chemical indicators, photo-sensitizers, MRI contrast enhancement agents and optical imaging dyes. In addition, its surface contains molecular targeting units, e.g. peptides or antibodies, as well as a cloaking agent, to prevent uptake by the immune system, i.e. enabling control of the plasma residence time. These dynamic nano-platforms (DNP) contain contrast enhancement agents for the imaging (MRI, optical, photo-acoustic) of targeted locations, i.e. tumors. Added to this are targeted therapy agents, such as photosensitizers for photodynamic therapy (PDT). A simple protocol, for rats implanted with human brain cancer, consists of tail injection with DNPs, followed by 5 min red light illumination of the tumor region. It resulted in excellent cure statistics for 9L glioblastoma.

  11. Brain tumor classification of microscopy images using deep residual learning

    Science.gov (United States)

    Ishikawa, Yota; Washiya, Kiyotada; Aoki, Kota; Nagahashi, Hiroshi

    2016-12-01

    The crisis rate of brain tumor is about one point four in ten thousands. In general, cytotechnologists take charge of cytologic diagnosis. However, the number of cytotechnologists who can diagnose brain tumors is not sufficient, because of the necessity of highly specialized skill. Computer-Aided Diagnosis by computational image analysis may dissolve the shortage of experts and support objective pathological examinations. Our purpose is to support a diagnosis from a microscopy image of brain cortex and to identify brain tumor by medical image processing. In this study, we analyze Astrocytes that is a type of glia cell of central nerve system. It is not easy for an expert to discriminate brain tumor correctly since the difference between astrocytes and low grade astrocytoma (tumors formed from Astrocyte) is very slight. In this study, we present a novel method to segment cell regions robustly using BING objectness estimation and to classify brain tumors using deep convolutional neural networks (CNNs) constructed by deep residual learning. BING is a fast object detection method and we use pretrained BING model to detect brain cells. After that, we apply a sequence of post-processing like Voronoi diagram, binarization, watershed transform to obtain fine segmentation. For classification using CNNs, a usual way of data argumentation is applied to brain cells database. Experimental results showed 98.5% accuracy of classification and 98.2% accuracy of segmentation.

  12. Brain imaging of pain: state of the art

    Science.gov (United States)

    Morton, Debbie L; Sandhu, Javin S; Jones, Anthony KP

    2016-01-01

    Pain is a complex sensory and emotional experience that is heavily influenced by prior experience and expectations of pain. Before the development of noninvasive human brain imaging, our grasp of the brain’s role in pain processing was limited to data from postmortem studies, direct recording of brain activity, patient experience and stimulation during neurosurgical procedures, and animal models of pain. Advances made in neuroimaging have bridged the gap between brain activity and the subjective experience of pain and allowed us to better understand the changes in the brain that are associated with both acute and chronic pain. Additionally, cognitive influences on pain such as attention, anticipation, and fear can now be directly observed, allowing for the interpretation of the neural basis of the psychological modulation of pain. The use of functional brain imaging to measure changes in endogenous neurochemistry has increased our understanding of how states of increased resilience and vulnerability to pain are maintained. PMID:27660488

  13. Whole brain imaging with Serial Two-Photon Tomography

    Directory of Open Access Journals (Sweden)

    Stephen P Amato

    2016-03-01

    Full Text Available Imaging entire mouse brains at submicron resolution has historically been a challenging undertaking and largely confined to the province of dedicated atlasing initiatives. The has limited systematic investigations into important areas of neuroscience, such as neural circuits, brain mapping and neurodegeneration. In this paper, we describe in detail Serial Two-Photon (STP tomography, a robust, reliable method for imaging entire brains with histological detail. We provide examples of how the basic methodology can be extended to other imaging modalities, such as optical coherence tomography, in order to provide unique contrast mechanisms. Furthermore we provide a survey of the research that STP tomography has enabled in the field of neuroscience, provide examples of how this technology enables quantitative whole brain studies, and discuss the current limitations of STP tomography-based approaches

  14. Photoacoustic imaging for transvascular drug delivery to the rat brain

    Science.gov (United States)

    Watanabe, Ryota; Sato, Shunichi; Tsunoi, Yasuyuki; Kawauchi, Satoko; Takemura, Toshiya; Terakawa, Mitsuhiro

    2015-03-01

    Transvascular drug delivery to the brain is difficult due to the blood-brain barrier (BBB). Thus, various methods for safely opening the BBB have been investigated, for which real-time imaging methods are desired both for the blood vessels and distribution of a drug. Photoacoustic (PA) imaging, which enables depth-resolved visualization of chromophores in tissue, would be useful for this purpose. In this study, we performed in vivo PA imaging of the blood vessels and distribution of a drug in the rat brain by using an originally developed compact PA imaging system with fiber-based illumination. As a test drug, Evans blue (EB) was injected to the tail vein, and a photomechanical wave was applied to the targeted brain tissue to increase the permeability of the blood vessel walls. For PA imaging of blood vessels and EB distribution, nanosecond pulses at 532 nm and 670 nm were used, respectively. We clearly visualized blood vessels with diameters larger than 50 μm and the distribution of EB in the brain, showing spatiotemporal characteristics of EB that was transvascularly delivered to the target tissue in the brain.

  15. DNA as sensors and imaging agents for metal ions.

    Science.gov (United States)

    Xiang, Yu; Lu, Yi

    2014-02-17

    Increasing interest in detecting metal ions in many chemical and biomedical fields has created demands for developing sensors and imaging agents for metal ions with high sensitivity and selectivity. This review covers recent progress in DNA-based sensors and imaging agents for metal ions. Through both combinatorial selection and rational design, a number of metal-ion-dependent DNAzymes and metal-ion-binding DNA structures that can selectively recognize specific metal ions have been obtained. By attachment of these DNA molecules with signal reporters such as fluorophores, chromophores, electrochemical tags, and Raman tags, a number of DNA-based sensors for both diamagnetic and paramagnetic metal ions have been developed for fluorescent, colorimetric, electrochemical, and surface Raman detection. These sensors are highly sensitive (with a detection limit down to 11 ppt) and selective (with selectivity up to millions-fold) toward specific metal ions. In addition, through further development to simplify the operation, such as the use of "dipstick tests", portable fluorometers, computer-readable disks, and widely available glucose meters, these sensors have been applied for on-site and real-time environmental monitoring and point-of-care medical diagnostics. The use of these sensors for in situ cellular imaging has also been reported. The generality of the combinatorial selection to obtain DNAzymes for almost any metal ion in any oxidation state and the ease of modification of the DNA with different signal reporters make DNA an emerging and promising class of molecules for metal-ion sensing and imaging in many fields of applications.

  16. Imaging brain tumor proliferative activity with [I-124]iododeoxyuridine

    NARCIS (Netherlands)

    Blasberg, RG; Roelcke, U; Weinreich, R; Beattie, B; von Ammon, K; Yonekawa, Y; Landolt, H; Guenther, [No Value; Crompton, NEA; Vontobel, P; Missimer, J; Maguire, RP; Koziorowski, J; Knust, EJ; Finn, RD; Leenders, KL

    2000-01-01

    Iododeoxyuridine (IUdR) uptake and retention was imaged by positron emission tomography (PET) at 0-48 min and 24 h after administration of 28.0-64.4 MBq (0.76-1.74 mCi) of [I-124]IUdR in 20 patients with brain tumors, including meningiomas and gliomas, The PET images were directly compared with gado

  17. Metabolic brain imaging correlated with clinical features of brain tumors

    Energy Technology Data Exchange (ETDEWEB)

    Alavi, J.; Alavi, A.; Dann, R.; Kushner, M.; Chawluk, J.; Powlis, W.; Reivich, M.

    1985-05-01

    Nineteen adults with brain tumors have been studied with positron emission tomography utilizing FDG. Fourteen had biopsy proven cerebral malignant glioma, one each had meningioma, hemangiopericytoma, primitive neuroectodermal tumor (PNET), two had unbiopsied lesions, and one patient had an area of biopsy proven radiation necrosis. Three different patterns of glucose metabolism are observed: marked increase in metabolism at the site of the known tumor in (10 high grade gliomas and the PNET), lower than normal metabolism at the tumor (in 1 grade II glioma, 3 grade III gliomas, 2 unbiopsied low density nonenhancing lesions, and the meningioma), no abnormality (1 enhancing glioma, the hemangiopericytoma and the radiation necrosis.) The metabolic rate of the tumor or the surrounding brain did not appear to be correlated with the history of previous irradiation or chemotherapy. Decreased metabolism was frequently observed in the rest of the affected hemisphere and in the contralateral cerebellum. Tumors of high grade or with enhancing CT characteristics were more likely to show increased metabolism. Among the patients with proven gliomas, survival after PETT scan tended to be longer for those with low metabolic activity tumors than for those with highly active tumors. The authors conclude that PETT may help to predict the malignant potential of tumors, and may add useful clinical information to the CT scan.

  18. Potential for photoacoustic imaging of the neonatal brain

    Science.gov (United States)

    Tavakolian, Pantea; Kosik, Ivan; Chamson-Reig, Astrid; St. Lawrence, Keith; Carson, Jeffrey J. L.

    2013-03-01

    Photoacoustic imaging (PAI) has been proposed as a non-invasive technique for imaging neonatal brain injury. Since PAI combines many of the merits of both optical and ultrasound imaging, images with high contrast, high resolution, and a greater penetration depth can be obtained when compared to more traditional optical methods. However, due to the strong attenuation and reflection of photoacoustic pressure waves at the skull bone, PAI of the brain is much more challenging than traditional methods (e.g. near infrared spectroscopy) for optical interrogation of the neonatal brain. To evaluate the potential limits the skull places on 3D PAI of the neonatal brain, we constructed a neonatal skull phantom (1.4-mm thick) with a mixture of epoxy and titanium dioxide powder that provided acoustic insertion loss (1-5MHz) similar to human infant skull bone. The phantom was molded into a realistic infant skull shape by means of a CNCmachined mold that was based upon a 3D CAD model. To evaluate the effect of the skull bone on PAI, a photoacoustic point source was raster scanned within the phantom brain cavity to capture the imaging operator of the 3D PAI system (128 ultrasound transducers in a hemispherical arrangement) with and without the intervening skull phantom. The resultant imaging operators were compared to determine the effect of the skull layer on the PA signals in terms of amplitude loss and time delay.

  19. Imaging Findings of Brain Death on 3-Tesla MRI

    Energy Technology Data Exchange (ETDEWEB)

    Sohn, Chul Ho [Dept. of Radiology, Seoul National University Hospital, Seoul National University College of Medicine, Seoul (Korea, Republic of); Lee, Hwa Pyung [Dept. of Occupational and Environmental Medicine, CHA Gumi Medical Center, CHA University, Gumi (Korea, Republic of); Park, Jun Beom [Dept. of Radiology, Korean Armed Force Daejeon Hospital, Daejeon (Korea, Republic of); Chang, Hyuk Won; Kim, Easlmaan; Park, Ui Jun; Kim, Hyoung Tae [Keimyung University College of Medicine, Dongsan Medical Center, Daegu (Korea, Republic of); Kim, Eun Hee [Dept. of Radiology, Seoul National University Bundang Hospital, Seongnam (Korea, Republic of); Ku, Jeong Hun [Dept. of Biomedical Engineering, Keimyung University College of Medicine, Daegu (Korea, Republic of)

    2012-09-15

    To demonstrate the usefulness of 3-tesla (3T) magnetic resonance imaging (MRI) including T2-weighted imaging (T2WI), diffusion weighted imaging (DWI), time-of-flight (TOF) magnetic resonance angiography (MRA), T2*-weighted gradient recalled echo (GRE), and susceptibility weighted imaging (SWI) in diagnosing brain death. Magnetic resonance imaging findings for 10 patients with clinically verified brain death (group I) and seven patients with comatose or stuporous mentality who did not meet the clinical criteria of brain death (group II) were retrospectively reviewed. Tonsilar herniation and loss of intraarterial flow signal voids (LIFSV) on T2WI were highly sensitive and specific findings for the diagnosis of brain death (p < 0.001 and < 0.001, respectively). DWI, TOF-MRA, and GRE findings were statistically different between the two groups (p = 0.015, 0.029, and 0.003, respectively). However, cortical high signal intensities in T2WI and SWI findings were not statistically different between the two group (p = 0.412 and 1.0, respectively). T2-weighted imaging, DWI, and MRA using 3T MRI may be useful for diagnosing brain death. However, SWI findings are not specific due to high false positive findings.

  20. Fuzzy local Gaussian mixture model for brain MR image segmentation.

    Science.gov (United States)

    Ji, Zexuan; Xia, Yong; Sun, Quansen; Chen, Qiang; Xia, Deshen; Feng, David Dagan

    2012-05-01

    Accurate brain tissue segmentation from magnetic resonance (MR) images is an essential step in quantitative brain image analysis. However, due to the existence of noise and intensity inhomogeneity in brain MR images, many segmentation algorithms suffer from limited accuracy. In this paper, we assume that the local image data within each voxel's neighborhood satisfy the Gaussian mixture model (GMM), and thus propose the fuzzy local GMM (FLGMM) algorithm for automated brain MR image segmentation. This algorithm estimates the segmentation result that maximizes the posterior probability by minimizing an objective energy function, in which a truncated Gaussian kernel function is used to impose the spatial constraint and fuzzy memberships are employed to balance the contribution of each GMM. We compared our algorithm to state-of-the-art segmentation approaches in both synthetic and clinical data. Our results show that the proposed algorithm can largely overcome the difficulties raised by noise, low contrast, and bias field, and substantially improve the accuracy of brain MR image segmentation.

  1. Regional localization of halopemide, a new psychotropic agent, in the rat brain

    NARCIS (Netherlands)

    Loonen, A.J.M.; Van Wijngaarden, I.; Janssen, P.A.J.; Soudijn, W.

    1978-01-01

    Halopemide is a new psychotropic agent, structurally related to the neuroleptics of the butyrophenone type, but with a different pharmacological and clinical profile. The concentration of halopemide in the rat brain is about 10 times less than that of R 29800, its chemical congener and of spiperone,

  2. Attenuation of Oxidative Damage by Boerhaavia diffusa L. Against Different Neurotoxic Agents in Rat Brain Homogenate.

    Science.gov (United States)

    Ayyappan, Prathapan; Palayyan, Salin Raj; Kozhiparambil Gopalan, Raghu

    2016-01-01

    Due to a high rate of oxidative metabolic activity in the brain, intense production of reactive oxygen metabolite occurs, and the subsequent generation of free radicals is implicated in the pathogenesis of traumatic brain injury, epilepsy, and ischemia as well as chronic neurodegenerative diseases. In the present study, protective effects of polyphenol rich ethanolic extract of Boerhaavia diffusa (BDE), a neuroprotective edible medicinal plant against oxidative stress induced by different neurotoxic agents, were evaluated. BDE was tested against quinolinic acid (QA), 3-nitropropionic acid (NPA), sodium nitroprusside (SNP), and Fe (II)/EDTA complex induced oxidative stress in rat brain homogenates. QA, NPA, SNP, and Fe (II)/EDTA treatment caused an increased level of thiobarbituric acid reactive substances (TBARS) in brain homogenates along with a decline in the activities of antioxidant enzymes. BDE treatment significantly decreased the production of TBARS (p tissues. Therefore, B. diffusa had high antioxidant potential that could inhibit the oxidative stress induced by different neurotoxic agents in brain. Since many of the neurological disorders are associated with free radical injury, these data may imply that B. diffusa, functioning as an antioxidant agent, may be beneficial for reducing various neurodegenerative complications.

  3. New calcium-selective smart contrast agents for magnetic resonance imaging.

    Science.gov (United States)

    Verma, Kirti Dhingra; Forgács, Attila; Uh, Hyounsoo; Beyerlein, Michael; Maier, Martin E; Petoud, Stéphane; Botta, Mauro; Logothetis, Nikos K

    2013-12-23

    Calcium plays a vital role in the human body and especially in the central nervous system. Precise maintenance of Ca(2+) levels is very crucial for normal cell physiology and health. The deregulation of calcium homeostasis can lead to neuronal cell death and brain damage. To study this functional role played by Ca(2+) in the brain noninvasively by using magnetic resonance imaging, we have synthesized a new set of Ca(2+) -sensitive smart contrast agents (CAs). The agents were found to be highly selective to Ca(2+) in the presence of other competitive anions and cations in buffer and in physiological fluids. The structure of CAs comprises Gd(3+)-DO3A (DO3A=1,4,7-tris(carboxymethyl)-1,4,7,10-tetraazacyclododecane) coupled to a Ca(2+) chelator o-amino phenol-N,N,O-triacetate (APTRA). The agents are designed to sense Ca(2+) present in extracellular fluid of the brain where its concentration is relatively high, that is, 1.2-0.8 mM. The determined dissociation constant of the CAs to Ca(2+) falls in the range required to sense and report changes in extracellular Ca(2+) levels followed by an increase in neural activity. In buffer, with the addition of Ca(2+) the increase in relaxivity ranged from 100-157%, the highest ever known for any T1-based Ca(2+)-sensitive smart CA. The CAs were analyzed extensively by the measurement of luminescence lifetime measurement on Tb(3+) analogues, nuclear magnetic relaxation dispersion (NMRD), and (17)O NMR transverse relaxation and shift experiments. The results obtained confirmed that the large relaxivity enhancement observed upon Ca(2+) addition is due to the increase of the hydration state of the complexes together with the slowing down of the molecular rotation and the retention of a significant contribution of the water molecules of the second sphere of hydration.

  4. Look again: effects of brain images and mind-brain dualism on lay evaluations of research.

    Science.gov (United States)

    Hook, Cayce J; Farah, Martha J

    2013-09-01

    Brain scans have frequently been credited with uniquely seductive and persuasive qualities, leading to claims that fMRI research receives a disproportionate share of public attention and funding. It has been suggested that functional brain images are fascinating because they contradict dualist beliefs regarding the relationship between the body and the mind. Although previous research has indicated that brain images can increase judgments of an article's scientific reasoning, the hypotheses that brain scans make research appear more interesting, surprising, or worthy of funding have not been tested. Neither has the relation between the allure of brain imaging and dualism. In the following three studies, laypersons rated both fictional research descriptions and real science news articles accompanied by brain scans, bar charts, or photographs. Across 988 participants, we found little evidence of neuroimaging's seductive allure or of its relation to self-professed dualistic beliefs. These results, taken together with other recent null findings, suggest that brain images are less powerful than has been argued.

  5. In vivo PET imaging of brain nicotinic cholinergic receptors

    Energy Technology Data Exchange (ETDEWEB)

    Bottlaender, M.; Valette, H.; Saba, W.; Schollhorn-Peyronneau, M.A.; Dolle, F.; Syrota, A. [Service Hospitalier Frederic Joliot (CEA/DSV/DRM), 91 - Orsay (France)

    2006-07-01

    Neuronal acetylcholine receptors (nAChRs) are widely distributed throughout the central nervous system where they modulate a number of CNS functions including neurotransmitter release, cognitive function, anxiety, analgesia and control of cerebral blood flow. In the brain, a major subtype is composed of the {alpha}4{beta}2 subunit combination. Density of this subtype has been shown to be decreased in patients with neuro-degenerative disease such as Alzheimer and Parkinson's disease (AD and PD), and mutated receptors has been described in some familial epilepsy. Thus, in vivo mapping of the nicotinic nAChRs by Positron Emission Tomography (PET) are of great interest to monitor the evolution of these pathologies and changes in the neuronal biochemistry induced by therapeutic agents. Recently, a new compound, 3-[2(S)-2-azetidinyl-methoxy]pyridine (A-85380) has been synthesised and labelled with fluorine-18, [{sup 18}F]fluoro-A-85380 (Dolle et al., 1999). The [{sup 18}F]fluoro-A-85380 has been shown to bind with high affinity t o nAChRs in vitro (Saba et al., 2004), and its toxicity was low and compatible with it s use at tracer dose in human PET studies (Valette, 2002). PET studies in baboons showed that, after in vivo administration of [ {sup 18}F]fluoro-A-85380 at a tracer dose, the distribution of the radioactivity in the brain reflect the distribution of the < 4R2 nAChRs. Competition and pre-blocking studies, using nicotinic agonists, confirm that the radiotracer binds specifically to the heteromeric nAChRs in the brain (Valette et al., 1999). The in vivo, characteristics of the [{sup 18}F]fluoro-A-8538 0 combined with its low toxicity make possible the imaging of the nicotinic receptor s in human by PET (Bottlaender 2003). Studies were performed in healthy non-smoker volunteers to evaluate the brain kinetics of [{sup 18}F]fluoro-A-85380 and to assess the quantification of its nAChRs binding in the human brain with PET (Gallezot et a., 2005). The [{sup 18}F

  6. Free radical reaction in ischemic rat brain. ESR-CT imaging

    Energy Technology Data Exchange (ETDEWEB)

    Kayama, Takamasa [Yamagata Univ. (Japan). School of Medicine

    1998-07-01

    Free radical change in images of rat brain during brain ischemia was observed by using a rapid scan L-band ESR-CT system. Male Wistar rats weighing 200 g were used. Rats were divided into three groups according to the duration of occlusion of 2, 4, and 8 hr as well as a control, sham-operated group. C-PROXYL dissolved in saline solution was used as an imaging agent and injected intraperitoneally in a volume of 3 ml at a concentration of 0.3 M at the beginning of reperfusion. ESR-CT imaging was performed 20 min after injection of C-PROXYL. In the sham-operated group, histological examination disclosed no ischemic lesion. Because C-PROXYL does not pass the blood-brain barrier, no brain image was obtained. In the 2 hr occlusion ischemic group, histological findings revealed spongioid change at the dorsal putamen. The ESR-CT image showed a small spot of uptake of nitroxide radicals in the area of the presumed left putamen which corresponded to the histological ischemic lesion. In the 8 hr occlusion group, the ischemic lesion was found even in the cerebral cortex. The image of nitroxide radical in the brain again closely corresponded to the histological ischemic area and occupied most of the left cerebral hemisphere. However, the area of ESR-CT image was wider than that of histological ischemic lesion. This may be because C-PROXYL leakage in the ischemic lesion diffuses and also because the extent of the efficiency of scavenging free radicals may decline. (K.H.)

  7. Near-infrared fluorescence heptamethine carbocyanine dyes mediate imaging and targeted drug delivery for human brain tumor

    Science.gov (United States)

    Wu, Jason Boyang; Shi, Changhong; Chu, Gina Chia-Yi; Xu, Qijin; Zhang, Yi; Li, Qinlong; Yu, John S.; Zhau, Haiyen E.; Chung, Leland W.K.

    2016-01-01

    Brain tumors and brain metastases are among the deadliest malignancies of all human cancers, largely due to the cellular blood-brain and blood-tumor barriers that limit the delivery of imaging and therapeutic agents from the systemic circulation to tumors. Thus, improved strategies for brain tumor visualization and targeted treatment are critically needed. Here we identified and synthesized a group of near-infrared fluorescence (NIRF) heptamethine carbocyanine dyes and derivative NIRF dye-drug conjugates for effective imaging and therapeutic targeting of brain tumors of either primary or metastatic origin in mice, which is mechanistically mediated by tumor hypoxia and organic aniontransporting polypeptide genes. We also demonstrate that these dyes, when conjugated to chemotherapeutic agents such as gemcitabine, significantly restricted the growth of both intracranial glioma xenografts and prostate tumor brain metastases and prolonged survival in mice. These results show promise in the application of NIRF dyes as novel theranostic agents for the detection and treatment of brain tumors. PMID:26197410

  8. Near-infrared fluorescence heptamethine carbocyanine dyes mediate imaging and targeted drug delivery for human brain tumor.

    Science.gov (United States)

    Wu, Jason Boyang; Shi, Changhong; Chu, Gina Chia-Yi; Xu, Qijin; Zhang, Yi; Li, Qinlong; Yu, John S; Zhau, Haiyen E; Chung, Leland W K

    2015-10-01

    Brain tumors and brain metastases are among the deadliest malignancies of all human cancers, largely due to the cellular blood-brain and blood-tumor barriers that limit the delivery of imaging and therapeutic agents from the systemic circulation to tumors. Thus, improved strategies for brain tumor visualization and targeted treatment are critically needed. Here we identified and synthesized a group of near-infrared fluorescence (NIRF) heptamethine carbocyanine dyes and derivative NIRF dye-drug conjugates for effective imaging and therapeutic targeting of brain tumors of either primary or metastatic origin in mice, which is mechanistically mediated by tumor hypoxia and organic anion-transporting polypeptide genes. We also demonstrate that these dyes, when conjugated to chemotherapeutic agents such as gemcitabine, significantly restricted the growth of both intracranial glioma xenografts and prostate tumor brain metastases and prolonged survival in mice. These results show promise in the application of NIRF dyes as novel theranostic agents for the detection and treatment of brain tumors.

  9. Identifying Brain Image Level Endophenotypes in Epilepsy

    CERN Document Server

    Cheng, Wei; Tian, Ge; Feng, Jianfeng; Wang, Zhengge; Zhang, Zhiqiang; Lu, GuangMing

    2012-01-01

    A brain wide association study (BWAS) based on the logistic regression was first developed and applied to a large population of epilepsy patients (168) and healthy controls (136). It was found that the most significant links associated with epilepsy are those bilateral links with regions mainly belonging to the default mode network and subcortex, such as amygdala, fusiform gyrus, inferior temporal gyrus, hippocampus, temporal pole, parahippocampal gyrus, insula, middle occipital gyrus, cuneus. These links were found to have much higher odd ratios than other links, and all of them showed reduced functional couplings in patients compared with controls. Interestingly, with the increasing of the seizure onset frequency or duration of illness, the functional connection between these bilateral regions became further reduced. On the other hand, as a functional compensation and brain plasticity, connections of these bilateral regions to other brain regions were abnormally enhanced and became even much stronger with t...

  10. Bypassing the blood-brain barrier: delivery of therapeutic agents by macrophages

    Science.gov (United States)

    Hirschberg, Henry; Baek, Seung-Kuk; Kwon, Young Jik; Sun, Chung-Ho; Madsen, Steen J.

    2010-02-01

    Introduction: Failure to eradicate infiltrating glioma cells using conventional treatment regimens results in tumor recurrence and is responsible for the dismal prognosis of patients with glioblastoma multiforme (GBM). This is due to the fact that these migratory cells are protected by the blood-brain barrier (BBB) and the blood brain tumor barrier (BBTB) which prevents the delivery of most anti-cancer agents. We have evaluated the ability of monocytes/macrophages (Mo/Ma) to cross the BBB in rats. This will permit access of anti-cancer agents such as nanoparticles to effectively target the infiltrating tumor cells, and potentially improve the treatment effectiveness for malignant gliomas. Materials and Methods: The infiltration of Mo/Ma into brain tumor spheroids in vitro was determined using fluorescent stained Mo/Ma. Tumors were also established in the brains of inbred rats and ALA-PDT was given 18 days following tumor induction. The degredation of the BBTB and quantification of the number of infiltrating Mo/Ma was examined on histological sections from removed brains. Results & Conclusion: PDT was highly effective in locally opening the BBTB and inducing macrophage migration into the irradiated portions of brain tumors.

  11. Rhesus monkey brain imaging through intact skull with thermoacoustic tomography

    OpenAIRE

    Xu, Yuan; Wang, Lihong V.

    2006-01-01

    Two-dimensional microwave-induced thermoacoustic tomography (TAT) is applied to imaging the Rhesus monkey brain through the intact skull. To reduce the wavefront distortion caused by the skull, only the low-frequency components of the thermoacoustic signals (< 1 MHz) are used to reconstruct the TAT images. The methods of signal processing and image reconstruction are validated by imaging a lamb kidney. The resolution of the system is found to be 4 mm when we image a 1-month-old monkey head co...

  12. Adaptive Intuitionistic Fuzzy Enhancement of Brain Tumor MR Images.

    Science.gov (United States)

    Deng, He; Deng, Wankai; Sun, Xianping; Ye, Chaohui; Zhou, Xin

    2016-10-27

    Image enhancement techniques are able to improve the contrast and visual quality of magnetic resonance (MR) images. However, conventional methods cannot make up some deficiencies encountered by respective brain tumor MR imaging modes. In this paper, we propose an adaptive intuitionistic fuzzy sets-based scheme, called as AIFE, which takes information provided from different MR acquisitions and tries to enhance the normal and abnormal structural regions of the brain while displaying the enhanced results as a single image. The AIFE scheme firstly separates an input image into several sub images, then divides each sub image into object and background areas. After that, different novel fuzzification, hyperbolization and defuzzification operations are implemented on each object/background area, and finally an enhanced result is achieved via nonlinear fusion operators. The fuzzy implementations can be processed in parallel. Real data experiments demonstrate that the AIFE scheme is not only effectively useful to have information from images acquired with different MR sequences fused in a single image, but also has better enhancement performance when compared to conventional baseline algorithms. This indicates that the proposed AIFE scheme has potential for improving the detection and diagnosis of brain tumors.

  13. Incidental ferumoxytol artifacts in clinical brain MR imaging

    Energy Technology Data Exchange (ETDEWEB)

    Bowser, Bruce A.; Campeau, Norbert G.; Carr, Carrie M.; Diehn, Felix E.; McDonald, Jennifer S.; Miller, Gary M.; Kaufmann, Timothy J. [Mayo Clinic, Department of Radiology, Rochester, MN (United States)

    2016-11-15

    Ferumoxytol (Feraheme) is a parenteral therapy approved for treatment of iron deficiency anemia. The product insert for ferumoxytol states that it may affect the diagnostic ability of MRI for up to 3 months. However, the expected effects may not be commonly recognized among clinical neuroradiologists. Our purpose is to describe the artifacts we have seen at our institution during routine clinical practice. We reviewed the patients at our institution that had brain MRI performed within 90 days of receiving intravenous ferumoxytol. The imaging was reviewed for specific findings, including diffusion-weighted imaging vascular susceptibility artifact, gradient-echo echo-planar T2*-weighted vascular susceptibility artifact, SWI/SWAN vascular susceptibility artifact, hypointense vascular signal on T2-weighted images, pre-gadolinium contrast vascular enhancement on magnetization-prepared rapid acquisition gradient echo (MPRAGE) imaging, and effects on post-gadolinium contrast T1 imaging. Multiple artifacts were observed in patients having a brain MRI within 3 days of receiving intravenous ferumoxytol. These included susceptibility artifact on DWI, GRE, and SWAN/SWI imaging, pre-gadolinium contrast increased vascular signal on MPRAGE imaging, and decreased expected enhancement on post-gadolinium contrast T1-weighted imaging. Ferumoxytol can create imaging artifacts which complicate clinical interpretation when brain MRI is performed within 3 days of administration. Recognition of the constellation of artifacts produced by ferumoxytol is important in order to obviate additional unnecessary examinations and mitigate errors in interpretation. (orig.)

  14. [Functional imaging of deep brain stimulation in idiopathic Parkinson's disease].

    Science.gov (United States)

    Hilker, R

    2010-10-01

    Functional brain imaging allows the effects of deep brain stimulation (DBS) on the living human brain to be investigated. In patients with advanced Parkinson's disease (PD), positron emission tomography (PET) studies were undertaken at rest as well as under motor, cognitive or behavioral activation. DBS leads to a reduction of abnormal PD-related network activity in the motor system, which partly correlates with the improvement of motor symptoms. The local increase of energy consumption within the direct target area suggests a predominant excitatory influence of the stimulation current on neuronal tissue. Remote effects of DBS of the subthalamic nucleus (STN) on frontal association cortices indicate an interference of stimulation energy with associative and limbic basal ganglia loops. Taken together, functional brain imaging provides very valuable data for advancement of the DBS technique in PD therapy.

  15. Human brain activity with functional NIR optical imager

    Science.gov (United States)

    Luo, Qingming

    2001-08-01

    In this paper we reviewed the applications of functional near infrared optical imager in human brain activity. Optical imaging results of brain activity, including memory for new association, emotional thinking, mental arithmetic, pattern recognition ' where's Waldo?, occipital cortex in visual stimulation, and motor cortex in finger tapping, are demonstrated. It is shown that the NIR optical method opens up new fields of study of the human population, in adults under conditions of simulated or real stress that may have important effects upon functional performance. It makes practical and affordable for large populations the complex technology of measuring brain function. It is portable and low cost. In cognitive tasks subjects could report orally. The temporal resolution could be millisecond or less in theory. NIR method will have good prospects in exploring human brain secret.

  16. A Novel imaging agent for acetylcholinesterase: 2-[F-18]fluoro-CP-118,954

    Energy Technology Data Exchange (ETDEWEB)

    Ryu, Y. K.; Choi, Y. S; Baek, J. Y.; Lee, K. H.; Choi, Y.; Kim, B. T [Sungkyunkwan University School of Medicine, Suwon (Korea, Republic of); Park, E. Y.; Kim, Y. R.; Kim, S. E [Seoul National University College of Medicine, Seoul (Korea, Republic of)

    2004-07-01

    AcetyIcholinesterase (AChE) is an important cholinergic marker for the diagnosis of Alzheimer's disease. Although many AChE inhibitors were developed as radioligands for AChE imaging, most of them showed a uniform regional brain distribution. In this study, 2-fluoro-CP-118,954 with excellent anti-AChE activity (IC{sub 50} = 0.74 nM) was prepared as the radioligand, 2-[F-18]fluoro-CP-118,954 ([F-l8]) and evaluated for AChE imaging. [F-l8] was prepared by reductive alkylation of CP-144,885 (Pfizer Inc. U.S.A.) with 2-[F-l8]fIuorobenzaldehyde at 130 .deg. for 15 min, followed by HPLC purification. Mice were injected with the radioligand [F-18] via tail vein. At the indicated time points (5, 15, 30, 60, 90 and 120 min), samples of bone and brain tissues were removed, weighed, and counted. Blocking experiments were carried out in mice by coinjection of the radioligand with, a dopamine receptor antagonist, or a sigma receptor agonist, and samples of brain tissues were collected at 60 min postinjection, weighed and counted. The radioligand [F-l8] was synthesized in 20-35% radiochemical yield and with high specific activity (40-42 GBq/mol). Tissue distribution studies demonstrated that the regional brain distribution of [F-18] was welI correlated with the known density of AChE in mouse brain, with the highest striatum to cerebellum uptake ratio (4.5) at 60 min postinjection. The high level of uptake was also shown at all time points in the olfactory tubercle that is known to have the dopaminergic neurons and also have high AChE staining in rat brain. The uptake in both the striatum and olfactory tubercle was not blocked by either dopamine receptor antagonists or a sigma receptor agonist. On the other hand, significant blocking of the uptake by suggested high specific binding of [F-l8] to AChE. This study demonstrated that [F-18] is a suitable imaging agent for AChE.

  17. Resolving brain regions using nanostructure initiator mass spectrometry imaging

    OpenAIRE

    Lee, Do Yup; Platt, Virginia; Bowen, Ben; Louie, Katherine; Canaria, Christie; McMurray, Cynthia T.; Northen, Trent

    2012-01-01

    Specific cell types are critically implicated in a variety of neuropathologies that exhibit region-specific susceptibility. Neuronal and glial function is impaired in a host of neurodegenerative diseases. Previous reports suggest that mass spectrometry imaging has the potential to resolve cell-specific enrichment in brain regions; however, individual ions cannot resolve glial and neuronal cells within the complex structure of brain tissue. Here, we utilized a matrix-free surface mass spectrom...

  18. Metabolic Syndrome, Brain Magnetic Resonance Imaging, and Cognition

    OpenAIRE

    2010-01-01

    OBJECTIVE We explored cognitive impairment in metabolic syndrome in relation to brain magnetic resonance imaging (MRI) findings. RESEARCH DESIGN AND METHODS We studied 819 participants free of clinical stroke and dementia of the population-based Austrian Stroke Prevention Study who had undergone brain MRI, neuropsychological testing, and a risk factor assessment relevant to National Cholesterol Education Program Adult Treatment Panel III criteria–defined metabolic syndrome. High-sensitivity C...

  19. Cerenkov and radioluminescence imaging of brain tumor specimens during neurosurgery

    Science.gov (United States)

    Spinelli, Antonello Enrico; Schiariti, Marco P.; Grana, Chiara M.; Ferrari, Mahila; Cremonesi, Marta; Boschi, Federico

    2016-05-01

    We presented the first example of Cerenkov luminescence imaging (CLI) and radioluminescence imaging (RLI) of human tumor specimens. A patient with a brain meningioma localized in the left parietal region was injected with 166 MBq of Y90-DOTATOC the day before neurosurgery. The specimens of the tumor removed during surgery were imaged using both CLI and RLI using an optical imager prototype developed in our laboratory. The system is based on a cooled electron multiplied charge coupled device coupled with an f/0.95 17-mm C-mount lens. We showed for the first time the possibility of obtaining CLI and RLI images of fresh human brain tumor specimens removed during neurosurgery.

  20. Double-echo perfusion-weighted MR imaging: basic concepts and application in brain tumors for the assessment of tumor blood volume and vascular permeability

    Energy Technology Data Exchange (ETDEWEB)

    Uematsu, Hidemasa [University of Fukui, Department of Radiology, Faculty of Medical Sciences, Fukui (Japan); Maeda, Masayuki [Mie University School of Medicine, Department of Radiology, Mie (Japan)

    2006-01-01

    Perfusion-weighted magnetic resonance (MR) imaging using contrast agents plays a key role in characterizing tumors of the brain. We have shown that double-echo perfusion-weighted MR imaging (DEPWI) is potentially useful in assessing brain tumors. Quantitative indices, such as tumor blood volume, are obtained using DEPWI, which allows correction of underestimation of tumor blood volume due to leakage of contrast agents from tumor vessels, in addition to simultaneous acquisition of tumor vessel permeability. This article describes basic concepts of DEPWI and demonstrates clinical applications in brain tumors. (orig.)

  1. NMR imaging of cell phone radiation absorption in brain tissue.

    Science.gov (United States)

    Gultekin, David H; Moeller, Lothar

    2013-01-02

    A method is described for measuring absorbed electromagnetic energy radiated from cell phone antennae into ex vivo brain tissue. NMR images the 3D thermal dynamics inside ex vivo bovine brain tissue and equivalent gel under exposure to power and irradiation time-varying radio frequency (RF) fields. The absorbed RF energy in brain tissue converts into Joule heat and affects the nuclear magnetic shielding and the Larmor precession. The resultant temperature increase is measured by the resonance frequency shift of hydrogen protons in brain tissue. This proposed application of NMR thermometry offers sufficient spatial and temporal resolution to characterize the hot spots from absorbed cell phone radiation in aqueous media and biological tissues. Specific absorption rate measurements averaged over 1 mg and 10 s in the brain tissue cover the total absorption volume. Reference measurements with fiber optic temperature sensors confirm the accuracy of the NMR thermometry.

  2. Brain magnetic resonance imaging of infants exposed prenatally to buprenorphine

    Energy Technology Data Exchange (ETDEWEB)

    Kahila, H.; Kivitie-Kallio, S.; Halmesmaki, E.; Valanne, L.; Autti, T. [Dept. of Obstetrics and Gynecology, Dept. of Pediatrics, and Helsinki Medical Imaging Center, Helsinki Univ. Central Hospital (Finland)

    2007-02-15

    Purpose: To evaluate the brains of newborns exposed to buprenorphine prenatally. Material and Methods: Seven neonates followed up antenatally in connection with their mothers' buprenorphine replacement therapy underwent 1.5T magnetic resonance imaging (MRI) of the brain before the age of 2 months. The infants were born to heavy drug abusers. Four mothers were hepatitis C positive, and all were HIV negative. All mothers smoked tobacco and used benzodiazepines. All pregnancies were full term, and no perinatal asphyxia occurred. All but one neonate had abstinence syndrome and needed morphine replacement therapy. Results: Neither structural abnormalities nor abnormalities in signal intensity were recorded. Conclusion: Buprenorphine replacement therapy does not seem to cause any major structural abnormalities of the brain, and it may prevent known hypoxic-ischemic brain changes resulting from uncontrolled drug abuse. Longitudinal studies are needed to assess possible abnormalities in the brain maturation process.

  3. Mapping fetal brain development in utero using magnetic resonance imaging: the Big Bang of brain mapping.

    Science.gov (United States)

    Studholme, Colin

    2011-08-15

    The development of tools to construct and investigate probabilistic maps of the adult human brain from magnetic resonance imaging (MRI) has led to advances in both basic neuroscience and clinical diagnosis. These tools are increasingly being applied to brain development in adolescence and childhood, and even to neonatal and premature neonatal imaging. Even earlier in development, parallel advances in clinical fetal MRI have led to its growing use as a tool in challenging medical conditions. This has motivated new engineering developments encompassing optimal fast MRI scans and techniques derived from computer vision, the combination of which allows full 3D imaging of the moving fetal brain in utero without sedation. These promise to provide a new and unprecedented window into early human brain growth. This article reviews the developments that have led us to this point, examines the current state of the art in the fields of fast fetal imaging and motion correction, and describes the tools to analyze dynamically changing fetal brain structure. New methods to deal with developmental tissue segmentation and the construction of spatiotemporal atlases are examined, together with techniques to map fetal brain growth patterns.

  4. Cross contrast multi-channel image registration using image synthesis for MR brain images.

    Science.gov (United States)

    Chen, Min; Carass, Aaron; Jog, Amod; Lee, Junghoon; Roy, Snehashis; Prince, Jerry L

    2017-02-01

    Multi-modal deformable registration is important for many medical image analysis tasks such as atlas alignment, image fusion, and distortion correction. Whereas a conventional method would register images with different modalities using modality independent features or information theoretic metrics such as mutual information, this paper presents a new framework that addresses the problem using a two-channel registration algorithm capable of using mono-modal similarity measures such as sum of squared differences or cross-correlation. To make it possible to use these same-modality measures, image synthesis is used to create proxy images for the opposite modality as well as intensity-normalized images from each of the two available images. The new deformable registration framework was evaluated by performing intra-subject deformation recovery, intra-subject boundary alignment, and inter-subject label transfer experiments using multi-contrast magnetic resonance brain imaging data. Three different multi-channel registration algorithms were evaluated, revealing that the framework is robust to the multi-channel deformable registration algorithm that is used. With a single exception, all results demonstrated improvements when compared against single channel registrations using the same algorithm with mutual information.

  5. Normal feline brain: clinical anatomy using magnetic resonance imaging.

    Science.gov (United States)

    Mogicato, G; Conchou, F; Layssol-Lamour, C; Raharison, F; Sautet, J

    2012-04-01

    The purpose of this study was to provide a clinical anatomy atlas of the feline brain using magnetic resonance imaging (MRI). Brains of twelve normal cats were imaged using a 1.5 T magnetic resonance unit and an inversion/recovery sequence (T1). Fourteen relevant MRI sections were chosen in transverse, dorsal, median and sagittal planes. Anatomic structures were identified and labelled using anatomical texts and Nomina Anatomica Veterinaria, sectioned specimen heads, and previously published articles. The MRI sections were stained according to the major embryological and anatomical subdivisions of the brain. The relevant anatomical structures seen on MRI will assist clinicians to better understand MR images and to relate this neuro-anatomy to clinical signs.

  6. Biodistribution of ultra small gadolinium-based nanoparticles as theranostic agent: application to brain tumors.

    Science.gov (United States)

    Miladi, Imen; Duc, Géraldine Le; Kryza, David; Berniard, Aurélie; Mowat, Pierre; Roux, Stéphane; Taleb, Jacqueline; Bonazza, Pauline; Perriat, Pascal; Lux, François; Tillement, Olivier; Billotey, Claire; Janier, Marc

    2013-09-01

    Gadolinium-based nanoparticles are novel objects with interesting physical properties, allowing their use for diagnostic and therapeutic applications. Gadolinium-based nanoparticles were imaged following intravenous injection in healthy rats and rats grafted with 9L gliosarcoma tumors using magnetic resonance imaging and scintigraphic imaging. Quantitative biodistribution using gamma-counting of each sampled organ confirmed that these nanoparticles were rapidly cleared essentially by renal excretion. Accumulation of these nanoparticles in 9L gliosarcoma tumors implanted in the rat brain was quantitated. This passive and long-duration accumulation of gadolinium-based nanoparticles in tumor, which is related to disruption of the blood-brain barrier, is in good agreement with the use of these nanoparticles as radiosensitizers for brain tumors.

  7. Characterization of nanoparticle-based contrast agents for molecular magnetic resonance imaging

    Science.gov (United States)

    Shan, Liang; Chopra, Arvind; Leung, Kam; Eckelman, William C.; Menkens, Anne E.

    2012-09-01

    The development of molecular imaging agents is currently undergoing a dramatic expansion. As of October 2011, 4,800 newly developed agents have been synthesized and characterized in vitro and in animal models of human disease. Despite this rapid progress, the transfer of these agents to clinical practice is rather slow. To address this issue, the National Institutes of Health launched the Molecular Imaging and Contrast Agents Database (MICAD) in 2005 to provide freely accessible online information regarding molecular imaging probes and contrast agents for the imaging community. While compiling information regarding imaging agents published in peer-reviewed journals, the MICAD editors have observed that some important information regarding the characterization of a contrast agent is not consistently reported. This makes it difficult for investigators to evaluate and meta-analyze data generated from different studies of imaging agents, especially for the agents based on nanoparticles. This article is intended to serve as a guideline for new investigators for the characterization of preclinical studies performed with nanoparticle-based MRI contrast agents. The common characterization parameters are summarized into seven categories: contrast agent designation, physicochemical properties, magnetic properties, in vitro studies, animal studies, MRI studies, and toxicity. Although no single set of parameters is suitable to define the properties of the various types of contrast agents, it is essential to ensure that these agents meet certain quality control parameters at the preclinical stage, so that they can be used without delay for clinical studies.

  8. High-throughput Identification of Phage-derived Imaging Agents

    Directory of Open Access Journals (Sweden)

    Kimberly A. Kelly

    2006-01-01

    Full Text Available The use of phage-displayed peptide libraries is a powerful method for selecting peptides with desired binding properties. However, the validation and prioritization of “hits” obtained from this screening approach remains challenging. Here, we describe the development and testing of a new analysis method to identify and display hits from phage-display experiments and high-throughput enzyme-linked immunosorbent assay screens. We test the method using a phage screen against activated macrophages to develop imaging agents with higher specificity for active disease processes. The new methodology should be useful in identifying phage hits and is extendable to other library screening methods such as small-molecule and nanoparticle libraries.

  9. Lesion detection in magnetic resonance brain images by hyperspectral imaging algorithms

    Science.gov (United States)

    Xue, Bai; Wang, Lin; Li, Hsiao-Chi; Chen, Hsian Min; Chang, Chein-I.

    2016-05-01

    Magnetic Resonance (MR) images can be considered as multispectral images so that MR imaging can be processed by multispectral imaging techniques such as maximum likelihood classification. Unfortunately, most multispectral imaging techniques are not particularly designed for target detection. On the other hand, hyperspectral imaging is primarily developed to address subpixel detection, mixed pixel classification for which multispectral imaging is generally not effective. This paper takes advantages of hyperspectral imaging techniques to develop target detection algorithms to find lesions in MR brain images. Since MR images are collected by only three image sequences, T1, T2 and PD, if a hyperspectral imaging technique is used to process MR images it suffers from the issue of insufficient dimensionality. To address this issue, two approaches to nonlinear dimensionality expansion are proposed, nonlinear correlation expansion and nonlinear band ratio expansion. Once dimensionality is expanded hyperspectral imaging algorithms are readily applied. The hyperspectral detection algorithm to be investigated for lesion detection in MR brain is the well-known subpixel target detection algorithm, called Constrained Energy Minimization (CEM). In order to demonstrate the effectiveness of proposed CEM in lesion detection, synthetic images provided by BrainWeb are used for experiments.

  10. Brain imaging, forward inference, and theories of reasoning.

    Science.gov (United States)

    Heit, Evan

    2014-01-01

    This review focuses on the issue of how neuroimaging studies address theoretical accounts of reasoning, through the lens of the method of forward inference (Henson, 2005, 2006). After theories of deductive and inductive reasoning are briefly presented, the method of forward inference for distinguishing between psychological theories based on brain imaging evidence is critically reviewed. Brain imaging studies of reasoning, comparing deductive and inductive arguments, comparing meaningful versus non-meaningful material, investigating hemispheric localization, and comparing conditional and relational arguments, are assessed in light of the method of forward inference. Finally, conclusions are drawn with regard to future research opportunities.

  11. Brain Imaging, Forward Inference, and Theories of Reasoning

    Directory of Open Access Journals (Sweden)

    Evan eHeit

    2015-01-01

    Full Text Available This review focuses on the issue of how neuroimaging studies address theoretical accounts of reasoning, through the lens of the method of forward inference (Henson, 2005, 2006. After theories of deductive and inductive reasoning are briefly presented, the method of forward inference for distinguishing between psychological theories based on brain imaging evidence is critically reviewed. Brain imaging studies of reasoning, comparing deductive and inductive arguments, comparing meaningful versus non-meaningful material, investigating hemispheric localization, and comparing conditional and relational arguments, are assessed in light of the method of forward inference. Finally, conclusions are drawn with regard to future research opportunities.

  12. In-vivo human brain molecular imaging with a brain-dedicated PET/MRI system.

    Science.gov (United States)

    Cho, Zang Hee; Son, Young Don; Choi, Eun Jung; Kim, Hang Keun; Kim, Jeong Hee; Lee, Sang Yoon; Ogawa, Seiji; Kim, Young Bo

    2013-02-01

    Advances in the new-generation of ultra-high-resolution, brain-dedicated positron emission tomography-magnetic resonance imaging (PET/MRI) systems have begun to provide many interesting insights into the molecular dynamics of the brain. First, the finely delineated structural information from ultra-high-field MRI can help us to identify accurate landmark structures, thereby making it easier to locate PET activation sites that are anatomically well-correlated with metabolic or ligand-specific organs in the neural structures in the brain. This synergistic potential of PET/MRI imaging is discussed in terms of neuroscience and neurological research from both translational and basic research perspectives. Experimental results from the hippocampus, thalamus, and brainstem obtained with (18)F-fluorodeoxyglucose and (11)C-3-amino-4-(2-dimethylaminomethylphenylsulfanyl)benzonitrile are used to demonstrate the potential of this new brain PET/MRI system.

  13. Functional magnetic resonance imaging and the brain: A brief review

    Science.gov (United States)

    Chow, Maggie S M; Wu, Sharon L; Webb, Sarah E; Gluskin, Katie; Yew, D T

    2017-01-01

    Functional magnetic resonance imaging (fMRI) is employed in many behavior analysis studies, with blood oxygen level dependent- (BOLD-) contrast imaging being the main method used to generate images. The use of BOLD-contrast imaging in fMRI has been refined over the years, for example, the inclusion of a spin echo pulse and increased magnetic strength were shown to produce better recorded images. Taking careful precautions to control variables during measurement, comparisons between different specimen groups can be illustrated by fMRI imaging using both quantitative and qualitative methods. Differences have been observed in comparisons of active and resting, developing and aging, and defective and damaged brains in various studies. However, cognitive studies using fMRI still face a number of challenges in interpretation that can only be overcome by imaging large numbers of samples. Furthermore, fMRI studies of brain cancer, lesions and other brain pathologies of both humans and animals are still to be explored. PMID:28144401

  14. Characterization of normal brain and brain tumor pathology by chisquares parameter maps of diffusion-weighted image data

    Energy Technology Data Exchange (ETDEWEB)

    Maier, Stephan E. E-mail: stephan@bwh.harvard.edu; Mamata, Hatsuho; Mulkern, Robert V

    2003-03-01

    Objective: To characterize normal and pathologic brain tissue by quantifying the deviation of diffusion-related signal from a simple monoexponential decay, when measured over a wider than usual range of b-factors. Methods and materials: Line scan diffusion imaging (LSDI), with diffusion weighting at multiple b-factors between 100 and 5000 s/mm{sup 2}, was performed on 1.5 T clinical scanners. Diffusion data of single slice sections were acquired in five healthy subjects and 19 brain tumor patients. In-patients, conventional T2-weighted and contrast-enhanced T1-weighted images were obtained for reference purposes. The chisquare ({chi}{sup 2}) error parameter associated with the monoexponential fits of the measured tissue water signals was then used to quantify the departure from a simple monoexponential signal decay on a pixel-by-pixel basis. Results: Diffusion-weighted images over a wider b-factor range than typically used were successfully obtained in all healthy subjects and patients. Normal and pathologic tissues demonstrated signal decays, which clearly deviate from a simple monoexponential behavior. The {chi}{sup 2} of cortical and deep grey matter was considerably lower than in white matter. In peritumoral edema, however, {chi}{sup 2} was 68% higher than in normal white matter. In highly malignant brain tumors, such as glioblastoma multiforme (GBM) or anaplastic astrocytoma, {chi}{sup 2} values were on average almost 400% higher than in normal white matter, while for one low grade astrocytoma and two cases of metastasis, {chi}{sup 2} was not profoundly different from the {chi}{sup 2} value of white matter. Maps of the {chi}{sup 2} values provide good visualization of spatial details. However, the tumor tissue contrast generated appeared in many cases to be different from the enhancement produced by paramagnetic contrast agents. For example, in cases where the contrast agent only highlighted the rim of the tumor, {chi}{sup 2} enhancement was present within the

  15. 3D Brain Tumors and Internal Brain Structures Segmentation in MR Images

    Directory of Open Access Journals (Sweden)

    P.NARENDRAN

    2012-02-01

    Full Text Available The main topic of this paper is to segment brain tumors, their components (edema and necrosis and internal structures of the brain in 3D MR images. For tumor segmentation we propose a framework that is a combination of region-based and boundary-based paradigms. In this framework, segment the brain using a method adapted for pathological cases and extract some global information on the tumor by symmetry based histogram analysis. We propose a new and original method that combines region and boundary information in two phases: initialization and refinement. The method relies on symmetry-based histogram analysis. The initial segmentation of the tumor is refined relying on boundary information of the image. We use a deformable model which is again constrained by the fused spatial relations of the structure. The method was also evaluated on 10 contrast enhanced T1-weighted images to segment the ventricles, caudate nucleus and thalamus.

  16. Different impressions of other agents obtained through social interaction uniquely modulate dorsal and ventral pathway activities in the social human brain.

    Science.gov (United States)

    Takahashi, Hideyuki; Terada, Kazunori; Morita, Tomoyo; Suzuki, Shinsuke; Haji, Tomoki; Kozima, Hideki; Yoshikawa, Masahiro; Matsumoto, Yoshio; Omori, Takashi; Asada, Minoru; Naito, Eiichi

    2014-09-01

    Internal (neuronal) representations in the brain are modified by our experiences, and this phenomenon is not unique to sensory and motor systems. Here, we show that different impressions obtained through social interaction with a variety of agents uniquely modulate activity of dorsal and ventral pathways of the brain network that mediates human social behavior. We scanned brain activity with functional magnetic resonance imaging (fMRI) in 16 healthy volunteers when they performed a simple matching-pennies game with a human, human-like android, mechanical robot, interactive robot, and a computer. Before playing this game in the scanner, participants experienced social interactions with each opponent separately and scored their initial impressions using two questionnaires. We found that the participants perceived opponents in two mental dimensions: one represented "mind-holderness" in which participants attributed anthropomorphic impressions to some of the opponents that had mental functions, while the other dimension represented "mind-readerness" in which participants characterized opponents as intelligent. Interestingly, this "mind-readerness" dimension correlated to participants frequently changing their game tactic to prevent opponents from envisioning their strategy, and this was corroborated by increased entropy during the game. We also found that the two factors separately modulated activity in distinct social brain regions. Specifically, mind-holderness modulated activity in the dorsal aspect of the temporoparietal junction (TPJ) and medial prefrontal and posterior paracingulate cortices, while mind-readerness modulated activity in the ventral aspect of TPJ and the temporal pole. These results clearly demonstrate that activity in social brain networks is modulated through pre-scanning experiences of social interaction with a variety of agents. Furthermore, our findings elucidated the existence of two distinct functional networks in the social human brain

  17. Targeted contrast agents--an adjunct to whole-body imaging: current concepts.

    Science.gov (United States)

    Foran, Paul; Bolster, Ferdia; Crosbie, Ian; MacMahon, Peter; O'Kennedy, Richard; Eustace, Stephen J

    2010-03-01

    This article reviews the potential use of a combination of whole-body imaging and targeted contrast agents in improving diagnostics, with a particular focus on oncology imaging. It looks at the rationale for nanoparticles and their development as targeted contrast agents. It subsequently describes many of the advances made thus far in developing tissue-specific contrast agents capable of targeting tumors that combined with whole-body imaging may enable superior cancer detection and characterization.

  18. In Vivo Brain MR Imaging at Subnanoliter Resolution: Contrast and Histology.

    Science.gov (United States)

    Watanabe, Takashi; Frahm, Jens; Michaelis, Thomas

    2016-01-01

    This article provides an overview of in vivo magnetic resonance (MR) imaging contrasts obtained for mammalian brain in relation to histological knowledge. Emphasis is paid to the (1) significance of high spatial resolution for the optimization of T1, T2, and magnetization transfer contrast, (2) use of exogenous extra- and intracellular contrast agents for validating endogenous contrast sources, and (3) histological structures and biochemical compounds underlying these contrasts and (4) their relevance to neuroradiology. Comparisons between MR imaging at subnanoliter resolution and histological data indicate that (a) myelin sheaths, (b) nerve cells, and (c) the neuropil are most responsible for observed MR imaging contrasts, while (a) diamagnetic macromolecules, (b) intracellular paramagnetic ions, and (c) extracellular free water, respectively, emerge as the dominant factors. Enhanced relaxation rates due to paramagnetic ions, such as iron and manganese, have been observed for oligodendrocytes, astrocytes, microglia, and blood cells in the brain as well as for nerve cells. Taken together, a plethora of observations suggests that the delineation of specific structures in high-resolution MR imaging of mammalian brain and the absence of corresponding contrasts in MR imaging of the human brain do not necessarily indicate differences between species but may be explained by partial volume effects. Second, paramagnetic ions are required in active cells in vivo which may reduce the magnetization transfer ratio in the brain through accelerated T1 recovery. Third, reductions of the magnetization transfer ratio may be more sensitive to a particular pathological condition, such as astrocytosis, microglial activation, inflammation, and demyelination, than changes in relaxation. This is because the simultaneous occurrence of increased paramagnetic ions (i.e., shorter relaxation times) and increased free water (i.e., longer relaxation times) may cancel T1 or T2 effects, whereas

  19. Brain imaging with synthetic MR in children: clinical quality assessment

    Energy Technology Data Exchange (ETDEWEB)

    Betts, Aaron M.; Serai, Suraj [Cincinnati Children' s Hospital Medical Center, Department of Radiology, Cincinnati, OH (United States); Leach, James L.; Jones, Blaise V. [Cincinnati Children' s Hospital Medical Center, Department of Radiology, Cincinnati, OH (United States); University of Cincinnati College of Medicine, Cincinnati, OH (United States); Zhang, Bin [Cincinnati Children' s Hospital Medical Center, Biostatistics and Epidemiology, Cincinnati, OH (United States)

    2016-10-15

    Synthetic magnetic resonance imaging is a quantitative imaging technique that measures inherent T1-relaxation, T2-relaxation, and proton density. These inherent tissue properties allow synthesis of various imaging sequences from a single acquisition. Clinical use of synthetic MR imaging has been described in adult populations. However, use of synthetic MR imaging has not been previously reported in children. The purpose of this study is to report our assessment of diagnostic image quality using synthetic MR imaging in children. Synthetic MR acquisition was obtained in a sample of children undergoing brain MR imaging. Image quality assessments were performed on conventional and synthetic T1-weighted, T2-weighted, and FLAIR images. Standardized linear measurements were performed on conventional and synthetic T2 images. Estimates of patient age based upon myelination patterns were also performed. Conventional and synthetic MR images were evaluated on 30 children. Using a 4-point assessment scale, conventional imaging performed better than synthetic imaging for T1-weighted, T2-weighted, and FLAIR images. When the assessment was simplified to a dichotomized scale, the conventional and synthetic T1-weighted and T2-weighted images performed similarly. However, the superiority of conventional FLAIR images persisted in the dichotomized assessment. There were no statistically significant differences between linear measurements made on T2-weighted images. Estimates of patient age based upon pattern of myelination were also similar between conventional and synthetic techniques. Synthetic MR imaging may be acceptable for clinical use in children. However, users should be aware of current limitations that could impact clinical utility in the software version used in this study. (orig.)

  20. CT versus MR in neonatal brain imaging at term

    Energy Technology Data Exchange (ETDEWEB)

    Robertson, Richard L.; Robson, Caroline D.; Zurakowski, David; Antiles, Sharon; Strauss, Keith; Mulkern, Robert V. [Department of Radiology, Children' s Hospital Medical Center, Harvard Medical School, 300 Longwood Avenue, MA 02115, Boston (United States)

    2003-07-01

    Recent reports have highlighted the lifetime risk of malignancy from using ionizing radiation in pediatric imaging. Computed tomography (CT), which uses ionizing radiation, is employed extensively for neonatal brain imaging of term infants. Magnetic resonance (MR) provides an alternative that does not use ionizing radiation. The purpose of this study was to assess the cross-modality agreement and interobserver agreement of CT and MR brain imaging of the term or near-term neonate. Brain CT and MR images of 48 neonates were retrospectively reviewed by two pediatric neuroradiologists. CT and MR examinations had been obtained within 72 h of one another in all patients. CT was obtained with 5 mm collimation (KV=120, mAs=340). MR consisted of T1-weighted imaging (TR/TE=300/14; 4-mm slice thickness/1-mm gap), T2-weighted imaging (TR/TE/etl= 3000/126/16; 4-mm slice thickness/1-mm gap), and line scan diffusion imaging (LSDI) (TR/TE/b factor=1258/63/750; nominal 4-mm slice thickness/3-mm gap). The brain was categorized as normal or abnormal on both CT and MR. Ischemic injury was the most common brain abnormality demonstrated. McNemar's test indicated no significant difference between CT and MR test results for reader 1 (P=0.22) or reader 2 (P=0.45). The readers agreed on the presence or absence of abnormality on CT in 40 patients (83.3%) and on MR in 45 patients (93.8%). For CT, the kappa coefficient indicated excellent interobserver agreement ({kappa}=0.68), although the lower limit of the 95% confidence interval extends to {kappa}=0.55, which indicates only good-to-moderate agreement. For MR, the kappa coefficient indicated almost perfect interobserver agreement ({kappa}=0.88) with the 95% confidence interval extending to a lower limit of {kappa}=0.76, which represents excellent agreement. Because MR demonstrates findings similar to CT and has greater interobserver agreement, it appears that MR is a superior test to CT in determining brain abnormalities in the term

  1. Structural Image Analysis of the Brain in Neuropsychology Using Magnetic Resonance Imaging (MRI) Techniques.

    Science.gov (United States)

    Bigler, Erin D

    2015-09-01

    Magnetic resonance imaging (MRI) of the brain provides exceptional image quality for visualization and neuroanatomical classification of brain structure. A variety of image analysis techniques provide both qualitative as well as quantitative methods to relate brain structure with neuropsychological outcome and are reviewed herein. Of particular importance are more automated methods that permit analysis of a broad spectrum of anatomical measures including volume, thickness and shape. The challenge for neuropsychology is which metric to use, for which disorder and the timing of when image analysis methods are applied to assess brain structure and pathology. A basic overview is provided as to the anatomical and pathoanatomical relations of different MRI sequences in assessing normal and abnormal findings. Some interpretive guidelines are offered including factors related to similarity and symmetry of typical brain development along with size-normalcy features of brain anatomy related to function. The review concludes with a detailed example of various quantitative techniques applied to analyzing brain structure for neuropsychological outcome studies in traumatic brain injury.

  2. Radiolabeled Apoptosis Imaging Agents for Early Detection of Response to Therapy

    Directory of Open Access Journals (Sweden)

    Kazuma Ogawa

    2014-01-01

    Full Text Available Since apoptosis plays an important role in maintaining homeostasis and is associated with responses to therapy, molecular imaging of apoptotic cells could be useful for early detection of therapeutic effects, particularly in oncology. Radiolabeled annexin V compounds are the hallmark in apoptosis imaging in vivo. These compounds are reviewed from the genesis of apoptosis (cell death imaging agents up to recent years. They have some disadvantages, including slow clearance and immunogenicity, because they are protein-based imaging agents. For this reason, several studies have been conducted in recent years to develop low molecule apoptosis imaging agents. In this review, radiolabeled phosphatidylserine targeted peptides, radiolabeled bis(zinc(II-dipicolylamine complex, radiolabeled 5-fluoropentyl-2-methyl-malonic acid (ML-10, caspase-3 activity imaging agents, radiolabeled duramycin, and radiolabeled phosphonium cation are reviewed as promising low-molecular-weight apoptosis imaging agents.

  3. Brain imaging of pain: state of the art

    Directory of Open Access Journals (Sweden)

    Morton DL

    2016-09-01

    Full Text Available Debbie L Morton, Javin S Sandhu, Anthony KP Jones Human Pain Research Group, Institute of Brain, Behaviour and Mental Health, University of Manchester, Manchester, UK Abstract: Pain is a complex sensory and emotional experience that is heavily influenced by prior experience and expectations of pain. Before the development of noninvasive human brain imaging, our grasp of the brain’s role in pain processing was limited to data from postmortem studies, direct recording of brain activity, patient experience and stimulation during neurosurgical procedures, and animal models of pain. Advances made in neuroimaging have bridged the gap between brain activity and the subjective experience of pain and allowed us to better understand the changes in the brain that are associated with both acute and chronic pain. Additionally, cognitive influences on pain such as attention, anticipation, and fear can now be directly observed, allowing for the interpretation of the neural basis of the psychological modulation of pain. The use of functional brain imaging to measure changes in endogenous neurochemistry has increased our understanding of how states of increased resilience and vulnerability to pain are maintained. Keywords: fMRI, PET, EEG, arthritis, fibromyalgia

  4. Diffusion-weighted imaging predicts cognition in pediatric brain injury.

    Science.gov (United States)

    Babikian, Talin; Tong, Karen A; Galloway, Nicholas R; Freier-Randall, Mary-Catherin; Obenaus, André; Ashwal, Stephen

    2009-12-01

    Apparent diffusion coefficient maps from diffusion-weighted imaging predict gross neurologic outcome in adults with traumatic brain injury. Few studies in children have been reported, and none have used apparent diffusion coefficient maps to predict long-term (>1 year) neurocognitive outcomes. In this study, pooled regional and total brain diffusion coefficients were used to predict long-term outcomes in 17 pediatric brain injury patients. Apparent diffusion coefficient values were grouped into peripheral and deep gray and white matter, posterior fossa, and total brain. Regions of interest excluded areas that appeared abnormal on T(2)-weighted images. Apparent diffusion coefficient values from peripheral regions were inversely correlated with cognitive functioning. No significant correlations were apparent between the cognitive scores and apparent diffusion coefficient values for deep tissue or the posterior fossa. Regression analyses suggested that combined peripheral gray and white matter apparent diffusion coefficients explained 42% of the variance in the combined neurocognitive index. Peripheral gray diffusion coefficients alone explained an additional 20% of variance after accounting for clinical variables. These results suggest that obtaining apparent diffusion coefficient values, specifically from peripheral brain regions, may predict long-term outcome after pediatric brain injury. Discrepancies in the literature on this topic, as well as possible explanations, including sampling and clinical considerations, are discussed.

  5. Reliability and Accuracy of Brain Volume Measurement on MR Imaging

    DEFF Research Database (Denmark)

    Yamagchii, Kechiro; Lassen, Anders; Ring, Poul

    1998-01-01

    Yamaguchi, K., Lassen, A. And Ring, P. Reliability and Accuracy of Brain Volume Measurement on MR Imaging. Abstract at ESMRMB98 European Society for Magnetic Resonance in Medicine and Biology, Geneva, Sept 17-20, 1998 Danish Research Center for Magnetic Resonance, Hvidovre University Hospital...

  6. Apparatus and method for motion tracking in brain imaging

    DEFF Research Database (Denmark)

    2013-01-01

    Disclosed is apparatus and method for motion tracking of a subject in medical brain imaging. The method comprises providing a light projector and a first camera; projecting a first pattern sequence (S1) onto a surface region of the subject with the light projector, wherein the subject is positioned...

  7. Quantitative analysis of brain magnetic resonance imaging for hepatic encephalopathy

    Science.gov (United States)

    Syh, Hon-Wei; Chu, Wei-Kom; Ong, Chin-Sing

    1992-06-01

    High intensity lesions around ventricles have recently been observed in T1-weighted brain magnetic resonance images for patients suffering hepatic encephalopathy. The exact etiology that causes magnetic resonance imaging (MRI) gray scale changes has not been totally understood. The objective of our study was to investigate, through quantitative means, (1) the amount of changes to brain white matter due to the disease process, and (2) the extent and distribution of these high intensity lesions, since it is believed that the abnormality may not be entirely limited to the white matter only. Eleven patients with proven haptic encephalopathy and three normal persons without any evidence of liver abnormality constituted our current data base. Trans-axial, sagittal, and coronal brain MRI were obtained on a 1.5 Tesla scanner. All processing was carried out on a microcomputer-based image analysis system in an off-line manner. Histograms were decomposed into regular brain tissues and lesions. Gray scale ranges coded as lesion were then brought back to original images to identify distribution of abnormality. Our results indicated the disease process involved pallidus, mesencephalon, and subthalamic regions.

  8. Power of the metaphor: forty signs on brain imaging.

    Science.gov (United States)

    Gocmen, Rahsan; Guler, Ezgi; Kose, Ilgaz Cagatay; Oguz, Kader K

    2015-01-01

    We retrospectively reviewed neuroradiology database at our tertiary-care hospital to search for patients with metaphoric or descriptive signs on brain computed tomography or magnetic resonance imaging. Only patients who had clinical or pathological definitive diagnosis were included in this review.

  9. Brain imaging in patients with freezing of gait

    NARCIS (Netherlands)

    Bartels, Anna L.; Leenders, Klaus L.

    2008-01-01

    Freezing of gait (FOG) is a disabling gait disturbance with unknown cerebral pathophysiology. In this review, we discuss the functional brain imaging Studies that address gait physiology and pathophysiology of FOG. Radiotracer metabolic studies show basal ganglia-cortical circuitry involvement in di

  10. Imaging Therapeutic PARP Inhibition In Vivo through Bioorthogonally Developed Companion Imaging Agents

    Directory of Open Access Journals (Sweden)

    Thomas Reiner

    2012-03-01

    Full Text Available A number of small-molecule poly (ADP-ribose polymerase (PARP inhibitors are currently undergoing advanced clinical trials. Determining the distribution and target inhibitory activity of these drugs in individual subjects, however, has proven problematic. Here, we used a PARP agent for positron emission tomography-computed tomography (PET-CT imaging (18F-BO, which we developed based on the Olaparib scaffold using rapid bioorthogonal conjugation chemistries. We show that the bioorthogonal 18F modification of the parent molecule is simple, highly efficient, and well tolerated, resulting in a half maximal inhibitory concentration (IC50 of 17.9 ± 1.1 nM. Intravital imaging showed ubiquitous distribution of the drug and uptake into cancer cells, with ultimate localization within the nucleus, all of which were inhibitable. Whole-body PET-CT imaging showed tumoral uptake of the drug, which decreased significantly, after a daily dose of Olaparib. Standard 18F-fludeoxyglucose imaging, however, failed to detect such therapy-induced changes. This research represents a step toward developing a more generic approach for the rapid codevelopment of companion imaging agents based on small-molecule therapeutic inhibitors.

  11. Evaluation of an automatic brain segmentation method developed for neonates on adult MR brain images

    Science.gov (United States)

    Moeskops, Pim; Viergever, Max A.; Benders, Manon J. N. L.; Išgum, Ivana

    2015-03-01

    Automatic brain tissue segmentation is of clinical relevance in images acquired at all ages. The literature presents a clear distinction between methods developed for MR images of infants, and methods developed for images of adults. The aim of this work is to evaluate a method developed for neonatal images in the segmentation of adult images. The evaluated method employs supervised voxel classification in subsequent stages, exploiting spatial and intensity information. Evaluation was performed using images available within the MRBrainS13 challenge. The obtained average Dice coefficients were 85.77% for grey matter, 88.66% for white matter, 81.08% for cerebrospinal fluid, 95.65% for cerebrum, and 96.92% for intracranial cavity, currently resulting in the best overall ranking. The possibility of applying the same method to neonatal as well as adult images can be of great value in cross-sectional studies that include a wide age range.

  12. Magnetic resonance imaging based noninvasive measurements of brain hemodynamics in neonates : A review

    NARCIS (Netherlands)

    De Vis, Jill B; Alderliesten, Thomas; Hendrikse, Jeroen; Petersen, Esben T; Benders, Manon Jnl

    2016-01-01

    Perinatal disturbances of brain hemodynamics can have a detrimental effect on the brain's parenchyma with consequently adverse neurodevelopmental outcome. Noninvasive, reliable tools to evaluate the neonate's brain hemodynamics are scarce. Advances in magnetic resonance imaging have provided new met

  13. Design Principles of Nanoparticles as Contrast Agents for Magnetic Resonance Imaging

    Science.gov (United States)

    Shan, Liang; Gu, Xinbin; Wang, Paul

    2013-09-01

    Molecular imaging is an emerging field that introduces molecular agents into traditional imaging techniques, enabling visualization, characterization and measurement of biological processes at the molecular and cellular levels in humans and other living systems. The promise of molecular imaging lies in its potential for selective potency by targeting biomarkers or molecular targets and the imaging agents serve as reporters for the selectivity of targeting. Development of an efficient molecular imaging agent depends on well-controlled high-quality experiment design involving target selection, agent synthesis, in vitro characterization, and in vivo animal characterization before it is applied in humans. According to the analysis from the Molecular Imaging and Contrast Agent Database (MICAD, books/NBK5330/">), more than 6000 molecular imaging agents with sufficient preclinical evaluation have been reported to date in the literature and this number increases by 250-300 novel agents each year. The majority of these agents are radionuclides, which are developed for positron emission tomography (PET) and single photon emission computed tomography (SPECT). Contrast agents for magnetic resonance imaging (MRI) account for only a small part. This is largely due to the fact that MRI is currently not a fully quantitative imaging technique and is less sensitive than PET and SPECT. However, because of the superior ability to simultaneously extract molecular and anatomic information, molecular MRI is attracting significant interest and various targeted nanoparticle contrast agents have been synthesized for MRI. The first and one of the most critical steps in developing a targeted nanoparticle contrast agent is target selection, which plays the central role and forms the basis for success of molecular imaging. This chapter discusses the design principles of targeted contrast agents in the emerging frontiers of molecular MRI.

  14. Molecular imaging of the brain. Using multi-quantum coherence and diagnostics of brain disorders

    Energy Technology Data Exchange (ETDEWEB)

    Kaila, M.M. [New South Wales Univ., Sydney, NSW (Australia). School of Physics; Kaila, Rakhi [Univ. of New South Wales, Sydney (Australia). School of Medicine

    2013-11-01

    Explains the basics of the MRI and its use in the diagnostics and the treatment of the human brain disorders. Examines multi-quantum magnetic resonance imaging methods and the diagnostics of brain disorders. Covers how in a non-invasive manner one can diagnose diseases of the brain. This book examines multi-quantum magnetic resonance imaging methods and the diagnostics of brain disorders. It consists of two Parts. The part I is initially devoted towards the basic concepts of the conventional single quantum MRI techniques. It is supplemented by the basic knowledge required to understand multi-quantum MRI. Practical illustrations are included both on recent developments in conventional MRI and the MQ-MRI. This is to illustrate the connection between theoretical concepts and their scope in the clinical applications. The Part II initially sets out the basic details about quadrupole charge distribution present in certain nuclei and their importance about the functions they perform in our brain. Some simplified final mathematical expressions are included to illustrate facts about the basic concepts of the quantum level interactions between magnetic dipole and the electric quadrupole behavior of useful nuclei present in the brain. Selected practical illustrations, from research and clinical practices are included to illustrate the newly emerging ideas and techniques. The reader should note that the two parts of the book are written with no interdependence. One can read them quite independently.

  15. Brain imaging of mild cognitive impairment and Alzheimer's disease

    Institute of Scientific and Technical Information of China (English)

    Changhao Yin; Siou Li; Weina Zhao; Jiachun Feng

    2013-01-01

    The rapidly increasing prevalence of cognitive impairment and Alzheimer's disease has the potential to create a major worldwide healthcare crisis. Structural MRI studies in patients with Alzheimer's disease and mild cognitive impairment are currently attracting considerable interest. It is extremely important to study early structural and metabolic changes, such as those in the hippocampus, entorhinal cortex, and gray matter structures in the medial temporal lobe, to allow the early detection of mild cognitive impairment and Alzheimer's disease. The microstructural integrity of white matter can be studied with diffusion tensor imaging. Increased mean diffusivity and decreased fractional anisotropy are found in subjects with white matter damage. Functional imaging studies with positron emission tomography tracer compounds enable detection of amyloid plaques in the living brain in patients with Alzheimer's disease. In this review, we will focus on key findings from brain imaging studies in mild cognitive impairment and Alzheimer's disease, including structural brain changes studied with MRI and white matter changes seen with diffusion tensor imaging, and other specific imaging methodologies will also be discussed.

  16. β淀粉样蛋白PET显像剂11C-DPOD的制备及其在动物体内的分布%Synthesis and Biological Evaluation of 11C-DPOD for PET Imaging Agent of Amyloid-β in Mouse Brain

    Institute of Scientific and Technical Information of China (English)

    王新艳; 张政伟; 蒋雨平; 孔艳艳; 桂媛; 胡名扬; 华逢春; 管一晖

    2013-01-01

    Aim To study the synthesis of 11C-labeled PET amyloid-P (Ap) imaging agent titled DPOD, a new series of 11C-6-OH-BTA-1 derivatives, and biological evaluation of 11C-DPOD for detecting amyloid-P plaques in mouse brain. Methods 11C-triflate-CH3 was bubbled into 2 mg precursor DPOD, which was dissolved in 0.1 mg methyl ethyl ketone, to generate 11C-DPOD in a V-tube at high temperature (about 80℃). The radiolabelled products were purified by HPLC. Then the image of radioactive concentration of transgenic, senile mice and rhesus monkey was made by using PET/CT. All data were analyzed by Stata 10.0 software (P<0.05). Results 11C-DPOD was a kind of colorless transparent liquid with ethyl alcohol about 10%, pH7.0. The radiochemical purity was over 95% and the average radiolabeling yield was from 10% to 15%. 11C-DPOD had the same effect as 11C-PIB in pharmacokinetics of transgenic and senile mice. Conclusion 11C-DPOD radioactivity of brain was synthesized by ourselves and washed out quickly thereafter in both transgenic mice and monkey.%目的 研究脑内β淀粉样蛋白(Aβ)的PET显像剂11C-DPOD即[N-甲基-11C]-3,5-二苯基-1,2,4-苯并噻唑的制备路线和在动物体内的分布情况.方法 使用11C-三氟甲基磺酰甲烷(11C-triflate-CH3)和2 mg自制DPOD前体(溶于0.1 mL丁酮中,摇匀后装于3mL的特制密闭反应瓶中,置-20℃)反应,在80℃水浴中对前体进行甲基化反应并完成11C标记.反应后的液体加入5mL注射用水稀释,过活化的固相C18柱除去杂质,再用乙醇0.5 mL洗脱保留在柱上的产品.经无菌注射水稀释和0.22 μm的微孔无菌滤膜过滤,得到澄清11C-DPOD乙醇水溶液.经尾静脉注射于转基因型阿尔茨海默病(AD)小鼠(AD小鼠)、正常C57老龄小鼠(正常老龄小鼠,作为对照);经肘静脉注射猕猴,进行动态显像.结果 11C-DPOD注射液为无色澄清透明液体(pH 7.0),含10%的乙醇,放射性化学纯度>98%,产率为10%~15%.在AD小鼠和正常

  17. Transport, monitoring, and successful brain MR imaging in unsedated neonates

    Energy Technology Data Exchange (ETDEWEB)

    Mathur, Amit M. [St. Louis Children' s Hospital at the Washington University School of Medicine, Department of Pediatrics and Newborn Medicine, St. Louis, MO (United States); St. Louis Children' s Hospital, Division of Newborn Medicine, St. Louis, MO (United States); Neil, Jeffrey J. [St. Louis Children' s Hospital at the Washington University School of Medicine, Department of Neurology, St. Louis, MO (United States); Mallinckrodt Institute of Radiology, St. Louis, MO (United States); McKinstry, Robert C. [Mallinckrodt Institute of Radiology, St. Louis, MO (United States); Inder, Terrie E. [St. Louis Children' s Hospital at the Washington University School of Medicine, Department of Pediatrics and Newborn Medicine, St. Louis, MO (United States); St. Louis Children' s Hospital at the Washington University School of Medicine, Department of Neurology, St. Louis, MO (United States); Mallinckrodt Institute of Radiology, St. Louis, MO (United States)

    2008-03-15

    Neonatal cerebral MR imaging is a sensitive technique for evaluating brain injury in the term and preterm infant. In term encephalopathic infants, MR imaging reliably detects not only the pattern of brain injury but might also provide clues about the timing of injury. In premature infants, MR imaging has surpassed US in the detection of white matter injury, a common lesion in this population. Concerns remain about the safety and transport of sedated neonates for MR examination to radiology suites, which are usually located at a distance from neonatal intensive care units. We present our own institutional experience and guidelines used to optimize the performance of cerebral MR examinations in neonates without sedation or anesthesia. (orig.)

  18. Regional manifold learning for deformable registration of brain MR images.

    Science.gov (United States)

    Ye, Dong Hye; Hamm, Jihun; Kwon, Dongjin; Davatzikos, Christos; Pohl, Kilian M

    2012-01-01

    We propose a method for deformable registration based on learning the manifolds of individual brain regions. Recent publications on registration of medical images advocate the use of manifold learning in order to confine the search space to anatomically plausible deformations. Existing methods construct manifolds based on a single metric over the entire image domain thus frequently miss regional brain variations. We address this issue by first learning manifolds for specific regions and then computing region-specific deformations from these manifolds. We then determine deformations for the entire image domain by learning the global manifold in such a way that it preserves the region-specific deformations. We evaluate the accuracy of our method by applying it to the LPBA40 dataset and measuring the overlap of the deformed segmentations. The result shows significant improvement in registration accuracy on cortex regions compared to other state of the art methods.

  19. An agent harms a victim: A functional magnetic resonance imaging study on specific moral emotions

    Energy Technology Data Exchange (ETDEWEB)

    Kedia, G. [INSERM, Inst Hlth et Med Res, U797, Res Unit Neuroimaging Psychiat, F-91401 Orsay (France); Kedia, G.; Martinot, J.L. [CEA, DSV, I2BM, SHFJ, Orsay (France); Kedia, G.; Martinot, J.L. [Univ Paris Sud, U797, Paris (France); Kedia, G.; Hilton, D. [Univ Toulouse, Toulouse (France); Berthoz, S. [Paris Descartes Univ, U797, Paris (France); Wessa, M. [Univ Heidelber, Cent Inst Mental Hlth, D-6800 Mannheim (Germany)

    2008-07-01

    The statement 'An agent harms a victim' depicts a situation that triggers moral emotions. Depending on whether the agent and the victim are the self or someone else, it can lead to four different moral emotions: self-anger ('I harm myself'), guilt ('I harm someone'), other-anger ('someone harms me'), and compassion ('someone harms someone'). In order to investigate the neural correlates of these emotions, we examined brain activation patterns elicited by variations in the agent (self vs. other) and the victim (self vs. other) of a harmful action. Twenty-nine healthy participants underwent functional magnetic resonance imaging while imagining being in situations in which they or someone else harmed themselves or someone else. Results indicated that the three emotional conditions associated with the involvement of other, either as agent or victim (guilt, other-anger, and compassion conditions), all activated structures that have been previously associated with the Theory of Mind (ToM, the attribution of mental states to others), namely, the dorsal medial prefrontal cortex, the precuneus, and the bilateral temporo-parietal junction. Moreover, the two conditions in which both the self and other were concerned by the harmful action (guilt and other-anger conditions) recruited emotional structures (i. e., the bilateral amygdala, anterior cingulate, and basal ganglia). These results suggest that specific moral emotions induce different neural activity depending on the extent to which they involve the self and other. (authors)

  20. Amide Proton Transfer (APT) MR imaging and Magnetization Transfer (MT) MR imaging of pediatric brain development

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Hong; Kang, Huiying; Peng, Yun [Beijing Children' s Hospital, Capital Medical University, Imaging Center, Department of Radiology, Beijing (China); Zhao, Xuna [Philips Healthcare, Beijing (China); Jiang, Shanshan; Zhang, Yi; Zhou, Jinyuan [Johns Hopkins University, Division of MR Research, Department of Radiology, Baltimore, MD (United States)

    2016-10-15

    To quantify the brain maturation process during childhood using combined amide proton transfer (APT) and conventional magnetization transfer (MT) imaging at 3 Tesla. Eighty-two neurodevelopmentally normal children (44 males and 38 females; age range, 2-190 months) were imaged using an APT/MT imaging protocol with multiple saturation frequency offsets. The APT-weighted (APTW) and MT ratio (MTR) signals were quantitatively analyzed in multiple brain areas. Age-related changes in MTR and APTW were evaluated with a non-linear regression analysis. The APTW signals followed a decreasing exponential curve with age in all brain regions measured (R{sup 2} = 0.7-0.8 for the corpus callosum, frontal and occipital white matter, and centrum semiovale). The most significant changes appeared within the first year. At maturation, larger decreases in APTW and lower APTW values were found in the white matter. On the contrary, the MTR signals followed an increasing exponential curve with age in the same brain regions measured, with the most significant changes appearing within the initial 2 years. There was an inverse correlation between the MTR and APTW signal intensities during brain maturation. Together with MT imaging, protein-based APT imaging can provide additional information in assessing brain myelination in the paediatric population. (orig.)

  1. Synthesis and evaluation of radioiodinated (S,S)-2-({alpha}-(2-iodophenoxy)benzyl)morpholine for imaging brain norepinephrine transporter

    Energy Technology Data Exchange (ETDEWEB)

    Kanegawa, Naoki; Kimura, Hiroyuki; Sugita, Taku; Kajiyama, Satomi; Kuge, Yuji; Saji, Hideo [Kyoto University, Department of Patho-Functional Bioanalysis, Graduate School of Pharmaceutical Sciences, Sakyo-ku, Kyoto (Japan); Kiyono, Yasushi [Kyoto University, Radioisotopes Research Laboratory, Kyoto University Hospital, Faculty of Medicine, Sakyo-ku, Kyoto (Japan); Kawashima, Hidekazu [Kyoto University, Department of Nuclear Medicine and Diagnostic Imaging, Graduate School of Medicine, Sakyo-ku, Kyoto (Japan); Ueda, Masashi [Kyoto Prefectural University of Medicine, Radioisotope Laboratory, Sakyo-ku, Kyoto (Japan)

    2006-06-15

    Abnormality of the brain norepinephrine transporter (NET) has been reported in several psychiatric and neuronal disorders. Since NET is an important target for the diagnosis of these diseases, the development of radiopharmaceuticals for imaging of brain NET has been eagerly awaited. In this study, we synthesized (S,S)-2-({alpha}-(2-iodophenoxy)benzyl)morpholine [(S,S)-IPBM], a derivative of reboxetine iodinated at position 2 of the phenoxy ring, and evaluated its potential as a radiopharmaceutical for imaging brain NET using SPECT. (S,S)-{sup 123/125}I-IPBM was synthesized in a halogen exchange reaction. The affinity and selectivity of (S,S)-IPBM for NET was measured by assaying the displacement of {sup 3}H-nisoxetine and (S,S)-{sup 125}I-IPBM from the binding site in rat brain membrane, respectively. The biodistribution of (S,S)-{sup 125}I-IPBM was also determined in rats. Furthermore, SPECT studies with (S,S)-{sup 123}I-IPBM were carried out in the common marmoset. (S,S)-{sup 125}I-IPBM was prepared with high radiochemical yields (65%) and high radiochemical purity (>98%). (S,S)-IPBM showed high affinity and selectivity for NET in the binding assay experiments. In biodistribution experiments, (S,S)-{sup 125}I-IPBM showed rapid uptake in the brain, and the regional cerebral distribution was consistent with the density of NET. The administration of nisoxetine, a selective NET-binding agent, decreased the accumulation of (S,S)-{sup 125}I-IPBM in the brain, but the administration of selective serotonin transporter and dopamine transporter binding agents caused no significant changes in the accumulation. Moreover, (S,S)-{sup 123}I-IPBM allowed brain NET imaging in the common marmoset with SPECT. These results suggest that (S,S)-{sup 123}I-IPBM is a potential SPECT radiopharmaceutical for imaging brain NET. (orig.)

  2. Reversible acute methotrexate leukoencephalopathy: atypical brain MR imaging features

    Energy Technology Data Exchange (ETDEWEB)

    Ziereisen, France; Damry, Nash; Christophe, Catherine [Queen Fabiola Children' s University Hospital, Department of Radiology, Brussels (Belgium); Dan, Bernard [Queen Fabiola Children' s University Hospital, Department of Neurology, Brussels (Belgium); Azzi, Nadira; Ferster, Alina [Queen Fabiola Children' s University Hospital, Department of Paediatrics, Brussels (Belgium)

    2006-03-15

    Unusual acute symptomatic and reversible early-delayed leukoencephalopathy has been reported to be induced by methotrexate (MTX). We aimed to identify the occurrence of such atypical MTX neurotoxicity in children and document its MR presentation. We retrospectively reviewed the clinical findings and brain MRI obtained in 90 children treated with MTX for acute lymphoblastic leukaemia or non-B malignant non-Hodgkin lymphoma. All 90 patients had normal brain imaging before treatment. In these patients, brain imaging was performed after treatment completion and/or relapse and/or occurrence of neurological symptoms. Of the 90 patients, 15 (16.7%) showed signs of MTX neurotoxicity on brain MRI, 9 (10%) were asymptomatic, and 6 (6.7%) showed signs of acute leukoencephalopathy. On the routine brain MRI performed at the end of treatment, all asymptomatic patients had classical MR findings of reversible MTX neurotoxicity, such as abnormal high-intensity areas localized in the deep periventricular white matter on T2-weighted images. In contrast, the six symptomatic patients had atypical brain MRI characterized by T2 high-intensity areas in the supratentorial cortex and subcortical white matter (n=6), cerebellar cortex and white matter (n=4), deep periventricular white matter (n=2) and thalamus (n=1). MR normalization occurred later than clinical recovery in these six patients. In addition to mostly asymptomatic classical MTX neurotoxicity, MTX may induce severe but reversible unusual leukoencephalopathy. It is important to recognize this clinicoradiological presentation in the differential diagnosis of acute neurological deterioration in children treated with MTX. (orig.)

  3. Intraoperative fluorescence imaging for personalized brain tumor resection: Current state and future directions

    Directory of Open Access Journals (Sweden)

    Evgenii Belykh

    2016-10-01

    Full Text Available Introduction: Fluorescence-guided surgery is one of the rapidly emerging methods of surgical theranostics. In this review, we summarize current fluorescence techniques used in neurosurgical practice for brain tumor patients, as well as future applications of recent laboratory and translational studies.Methods: Review of the literature.Results: A wide spectrum of fluorophores that have been tested for brain surgery is reviewed. Beginning with a fluorescein sodium application in 1948 by Moore, fluorescence guided brain tumor surgery is either routinely applied in some centers or is under active study in clinical trials. Besides the trinity of commonly used drugs (fluorescein sodium, 5-ALA and ICG, less studied fluorescent stains, such as tetracyclines, cancer-selective alkylphosphocholine analogs, cresyl violet, acridine orange, and acriflavine can be used for rapid tumor detection and pathological tissue examination. Other emerging agents such as activity-based probes and targeted molecular probes that can provide biomolecular specificity for surgical visualization and treatment are reviewed. Furthermore, we review available engineering and optical solutions for fluorescent surgical visualization. Instruments for fluorescent-guided surgery are divided into wide-field imaging systems and hand-held probes. Recent advancements in quantitative fluorescence-guided surgery are discussed.Conclusion: We are standing on the doorstep of the era of marker-assisted tumor management. Innovations in the fields of surgical optics, computer image analysis, and molecular bioengineering are advancing fluorescence-guided tumor resection paradigms, leading to cell-level approaches to visualization and resection of brain tumors.

  4. Multi-stimuli responsive Cu2S nanocrystals as trimodal imaging and synergistic chemo-photothermal therapy agents

    Science.gov (United States)

    Poulose, Aby Cheruvathoor; Veeranarayanan, Srivani; Mohamed, M. Sheikh; Nagaoka, Yutaka; Romero Aburto, Rebeca; Mitcham, Trevor; Ajayan, Pulickel M.; Bouchard, Richard R.; Sakamoto, Yasushi; Yoshida, Yasuhiko; Maekawa, Toru; Sakthi Kumar, D.

    2015-04-01

    A size and shape tuned, multifunctional metal chalcogenide, Cu2S-based nanotheranostic agent is developed for trimodal imaging and multimodal therapeutics against brain cancer cells. This theranostic agent was highly efficient in optical, photoacoustic and X-ray contrast imaging systems. The folate targeted NIR-responsive photothermal ablation in synergism with the chemotherapeutic action of doxorubicin proved to be a rapid precision guided cancer-killing module. The multi-stimuli, i.e., pH-, thermo- and photo-responsive drug release behavior of the nanoconjugates opens up a wider corridor for on-demand triggered drug administration. The simple synthesis protocol, combined with the multitudes of interesting features packed into a single nanoformulation, clearly demonstrates the competing role of this Cu2S nanosystem in future cancer treatment strategies.A size and shape tuned, multifunctional metal chalcogenide, Cu2S-based nanotheranostic agent is developed for trimodal imaging and multimodal therapeutics against brain cancer cells. This theranostic agent was highly efficient in optical, photoacoustic and X-ray contrast imaging systems. The folate targeted NIR-responsive photothermal ablation in synergism with the chemotherapeutic action of doxorubicin proved to be a rapid precision guided cancer-killing module. The multi-stimuli, i.e., pH-, thermo- and photo-responsive drug release behavior of the nanoconjugates opens up a wider corridor for on-demand triggered drug administration. The simple synthesis protocol, combined with the multitudes of interesting features packed into a single nanoformulation, clearly demonstrates the competing role of this Cu2S nanosystem in future cancer treatment strategies. Electronic supplementary information (ESI) available: Methodology and additional experimental results. See DOI: 10.1039/c4nr07139e

  5. New perspectives on using brain imaging to study CNS stimulants.

    Science.gov (United States)

    Lukas, Scott E

    2014-12-01

    While the recent application of brain imaging to study CNS stimulants has offered new insights into the fundamental factors that contribute to their use and abuse, many gaps remain. Brain circuits that mediate pleasure, dependence, craving and relapse are anatomically, neurophysiologically and neurochemically distinct from one another, which has guided the search for correlates of stimulant-seeking and taking behavior. However, unlike other drugs of abuse, metrics for tolerance and physical dependence on stimulants are not obvious. The dopamine theory of stimulant abuse does not sufficiently explain this disorder as serotonergic, GABAergic and glutamagergic circuits are clearly involved in stimulant pharmacology and so tracking the source of the "addictive" processes must adopt a more multimodal, multidisciplinary approach. To this end, both anatomical and functional magnetic resonance imaging (MRI), MR spectroscopy (MRS) and positron emission tomography (PET) are complementary and have equally contributed to our understanding of how stimulants affect the brain and behavior. New vistas in this area include nanotechnology approaches to deliver small molecules to receptors and use MRI to resolve receptor dynamics. Anatomical and blood flow imaging has yielded data showing that cognitive enhancers might be useful adjuncts in treating CNS stimulant dependence, while MRS has opened opportunities to examine the brain's readiness to accept treatment as GABA tone normalizes after detoxification. A desired outcome of the above approaches is being able to offer evidence-based rationales for treatment approaches that can be implemented in a more broad geographic area, where access to brain imaging facilities may be limited. This article is part of the Special Issue entitled 'CNS Stimulants'.

  6. Laser speckle-imaging of blood microcirculation in the brain cortex of laboratory rats in stress

    Energy Technology Data Exchange (ETDEWEB)

    Vilensky, M A; Semyachkina-Glushkovskaya, Oxana V; Timoshina, P A; Kuznetsova, Jana V; Semyachkin-Glushkovskii, I A; Agafonov, Dmitry N; Tuchin, Valerii V

    2012-06-30

    The results of experimental approbation of the method of laser full-field speckle-imaging for monitoring the changes in blood microcirculation state of the brain cortex of laboratory rats under the conditions of developing stroke and administration of vasodilating and vasoconstrictive agents are presented. The studies aimed at the choice of the optimal conditions of speckle-image formation and recording were performed and the software implementing an adaptive algorithm for processing the data of measurements was created. The transfer of laser radiation to the probed region of the biotissue was implemented by means of a silica-polymer optical fibre. The problems and prospects of speckle-imaging of cerebral microcirculation of blood in laboratory and clinical conditions are discussed.

  7. Limitations of Sulforhodamine 101 for Brain Imaging

    Science.gov (United States)

    Hülsmann, Swen; Hagos, Liya; Heuer, Heike; Schnell, Christian

    2017-01-01

    Since 2004, the red fluorescent dye Sulforhodamine 101 (SR101) has been boosting the functional analysis of astrocytes in a functional environment in an unprecedented way. However, two major limitations have been challenging the usefulness of this tool for cellular imaging: (i) SR101 is not as specific for astrocytes as previously reported; and (ii) discoveries of severe excitatory side effects of SR101 are bearing the risk of unwanted alteration of the system of interest. In this article, we summarize the current knowledge about SR101-labeling protocols and discuss the problems that arise from varying of the staining protocols. Furthermore, we provide a testable hypothesis for the observed hyper-excitability that can be observed when using SR101.

  8. Positron emission tomography imaging of (2R,3R)-5-[{sup 18}F]fluoroethoxybenzovesamicol in rat and monkey brain: a radioligand for the vesicular acetylcholine transporter

    Energy Technology Data Exchange (ETDEWEB)

    Kilbourn, Michael R. [Division of Nuclear Medicine, Department of Radiology, University of Michigan School of Medicine, Ann Arbor, MI 48109 (United States)], E-mail: mkilbour@umich.edu; Hockley, Brian; Lee, Lihsueh; Sherman, Phillip; Quesada, Carole; Frey, Kirk A.; Koeppe, Robert A. [Division of Nuclear Medicine, Department of Radiology, University of Michigan School of Medicine, Ann Arbor, MI 48109 (United States)

    2009-07-15

    Introduction: The regional brain distribution of (2R,3R)-5-[{sup 18}F]fluoroethoxy-benzovesamicol ((-)-[{sup 18}F]FEOBV), a radioligand for the vesicular acetylcholine transporter (VAChT), was examined in vivo in mice, rats and rhesus monkeys. Methods: Regional brain distributions of (-)-[{sup 18}F]FEOBV in mice were determined using ex vivo dissection. MicroPET imaging was used to determine the regional brain pharmacokinetics of the radioligand in rat and rhesus monkey brains. Results: In all three species, clear heterogeneous regional brain distributions were obtained, with the rank order of brain tissues (striatum>thalamus>cortex>cerebellum) consistent with the distribution of cholinergic nerve terminals containing the VAChT. Conclusions: (-)-[{sup 18}F]FEOBV remains a viable candidate for further development as an in vivo imaging agent for positron emission tomography (PET) studies of the VAChT in the human brain.

  9. A Primer on Brain Imaging in Developmental Psychopathology: What Is It Good For?

    Science.gov (United States)

    Pine, Daniel S.

    2006-01-01

    This primer introduces a Special Section on brain imaging, which includes a commentary and 10 data papers presenting applications of brain imaging to questions on developmental psychopathology. This primer serves two purposes. First, the article summarizes the strength and weaknesses of various brain-imaging techniques typically employed in…

  10. Implementing Tumor Detection and Area Calculation in Mri Image of Human Brain Using Image Processing Techniques

    Directory of Open Access Journals (Sweden)

    Sunil L. Bangare

    2015-04-01

    Full Text Available This paper is based on the research on Human Brain Tumor which uses the MRI imaging technique to capture the image. In this proposed work Brain Tumor area is calculated to define the Stage or level of seriousness of the tumor. Image Processing techniques are used for the brain tumor area calculation and Neural Network algorithms for the tumor position calculation. Also in the further advancement the classification of the tumor based on few parameters is also expected. Proposed work is divided in to following Modules: Module 1: Image Pre-Processing Module 2: Feature Extraction, Segmentation using K-Means Algorithm and Fuzzy C-Means Algorithm Module 3: Tumor Area calculation & Stage detection Module 4: Classification and position calculation of tumor using Neural Network

  11. Radionuclide brain imaging in acquired immunodeficiency syndrome (AIDS)

    Energy Technology Data Exchange (ETDEWEB)

    Costa, D.C.; Gacinovic, S.; Miller, R.F. [London University College Medical School, Middlesex Hospital, London (United Kingdom)

    1995-09-01

    Infection with the Human Immunodeficiency Virus type 1 (HIV-1) may produce a variety of central nervous system (CNS) symptoms and signs. CNS involvement in patients with the Acquired Immunodeficiency Syndrome (AIDS) includes AIDS dementia complex or HIV-1 associated cognitive/motor complex (widely known as HIV encephalopathy), progressive multifocal leucoencephalopathy (PML), opportunistic infections such as Toxoplasma gondii, TB, Cryptococcus and infiltration by non-Hodgkin`s B cell lymphoma. High resolution structural imaging investigations, either X-ray Computed Tomography (CT scan) or Magnetic Resonance Imaging (MRI) have contributed to the understanding and definition of cerebral damage caused by HIV encephalopathy. Atrophy and mainly high signal scattered white matter abnormalities are commonly seen with MRI. PML produces focal white matter high signal abnormalities due to multiple foci of demyelination. However, using structural imaging techniques there are no reliable parameters to distinguish focal lesions due to opportunistic infection (Toxoplasma gondii abscess) from neoplasm (lymphoma infiltration). It is studied the use of radionuclide brain imaging techniques in the investigation of HIV infected patients. Brain perfusion Single Photon Emission Tomography (SPET), neuroreceptor and Positron Emission Tomography (PET) studies are reviewed. Greater emphasis is put on the potential of some radiopharmaceuticals, considered to be brain tumour markers, to distinguish intracerebral lymphoma infiltration from Toxoplasma infection. SPET with {sup 201}Tl using quantification (tumour to non-tumour radioactivity ratios) appears a very promising technique to identify intracerebral lymphoma.

  12. Dye-Enhanced Multimodal Confocal Imaging of Brain Cancers

    Science.gov (United States)

    Wirth, Dennis; Snuderl, Matija; Sheth, Sameer; Curry, William; Yaroslavsky, Anna

    2011-04-01

    Background and Significance: Accurate high resolution intraoperative detection of brain tumors may result in improved patient survival and better quality of life. The goal of this study was to evaluate dye enhanced multimodal confocal imaging for discriminating normal and cancerous brain tissue. Materials and Methods: Fresh thick brain specimens were obtained from the surgeries. Normal and cancer tissues were investigated. Samples were stained in methylene blue and imaged. Reflectance and fluorescence signals were excited at 658nm. Fluorescence emission and polarization were registered from 670 nm to 710 nm. The system provided lateral resolution of 0.6 μm and axial resolution of 7 μm. Normal and cancer specimens exhibited distinctively different characteristics. H&E histopathology was processed from each imaged sample. Results and Conclusions: The analysis of normal and cancerous tissues indicated clear differences in appearance in both the reflectance and fluorescence responses. These results confirm the feasibility of multimodal confocal imaging for intraoperative detection of small cancer nests and cells.

  13. Automatic segmentation of brain images: selection of region extraction methods

    Science.gov (United States)

    Gong, Leiguang; Kulikowski, Casimir A.; Mezrich, Reuben S.

    1991-07-01

    In automatically analyzing brain structures from a MR image, the choice of low level region extraction methods depends on the characteristics of both the target object and the surrounding anatomical structures in the image. The authors have experimented with local thresholding, global thresholding, and other techniques, using various types of MR images for extracting the major brian landmarks and different types of lesions. This paper describes specifically a local- binary thresholding method and a new global-multiple thresholding technique developed for MR image segmentation and analysis. The initial testing results on their segmentation performance are presented, followed by a comparative analysis of the two methods and their ability to extract different types of normal and abnormal brain structures -- the brain matter itself, tumors, regions of edema surrounding lesions, multiple sclerosis lesions, and the ventricles of the brain. The analysis and experimental results show that the global multiple thresholding techniques are more than adequate for extracting regions that correspond to the major brian structures, while local binary thresholding is helpful for more accurate delineation of small lesions such as those produced by MS, and for the precise refinement of lesion boundaries. The detection of other landmarks, such as the interhemispheric fissure, may require other techniques, such as line-fitting. These experiments have led to the formulation of a set of generic computer-based rules for selecting the appropriate segmentation packages for particular types of problems, based on which further development of an innovative knowledge- based, goal directed biomedical image analysis framework is being made. The system will carry out the selection automatically for a given specific analysis task.

  14. Radiolabelled D/sub 2/ agonists as prolactinoma imaging agents: Progress report for period February 1, 1988--January 31, 1989

    Energy Technology Data Exchange (ETDEWEB)

    Otto, C.A.

    1988-10-15

    Targeted studies completed include the evaluation of tritiated N-0437, evaluation of /sup 35/S-cysteamine, evaluation of /sup 18/F-FDG and initiation of synthetic efforts towards the synthesis of iodinated N-0437 and pergolide analogs. The direction of the project has been changed due to several factors which include the decided lack of favorable experimental results, the excellence of results using muscarinic receptor ligands in pituitary, brain and heart and the contention of the DOE review panel that the original grant proposal was based on flawed assumptions together with their perceived lack of importance to pituitary imaging. In the final year of this grant, three studies will be completed. The first study is the continuation of synthetic efforts to prepare iodinated N-0437 and pergolide analogs for possible use as brain imaging agents. The second study is directed towards completion of biochemical evaluation of various muscarinic receptor analogs for heart, brain and (possible) pituitary imaging. The third study is to probe the use of quaternized D/sub 2/ receptor ligands for imaging peripheral dopaminergic receptors (including the pituitary). 14 refs., 1 fig., 7 tabs.

  15. Role of infectious agents in the carcinogenesis of brain and head and neck cancers

    Directory of Open Access Journals (Sweden)

    Alibek Kenneth

    2013-02-01

    Full Text Available Abstract This review concentrates on tumours that are anatomically localised in head and neck regions. Brain cancers and head and neck cancers together account for more than 873,000 cases annually worldwide, with an increasing incidence each year. With poor survival rates at late stages, brain and head and neck cancers represent serious conditions. Carcinogenesis is a multi-step process and the role of infectious agents in this progression has not been fully identified. A major problem with such research is that the role of many infectious agents may be underestimated due to the lack of or inconsistency in experimental data obtained globally. In the case of brain cancer, no infection has been accepted as directly oncogenic, although a number of viruses and parasites are associated with the malignancy. Our analysis of the literature showed the presence of human cytomegalovirus (HCMV in distinct types of brain tumour, namely glioblastoma multiforme (GBM and medulloblastoma. In particular, there are reports of viral protein in up to 100% of GBM specimens. Several epidemiological studies reported associations of brain cancer and toxoplasmosis seropositivity. In head and neck cancers, there is a distinct correlation between Epstein-Barr virus (EBV and nasopharyngeal carcinoma (NPC. Considering that almost every undifferentiated NPC is EBV-positive, virus titer levels can be measured to screen high-risk populations. In addition there is an apparent association between human papilloma virus (HPV and head and neck squamous cell carcinoma (HNSCC; specifically, 26% of HNSCCs are positive for HPV. HPV type 16 was the most common type detected in HNSCCs (90% and its dominance is even greater than that reported in cervical carcinoma. Although there are many studies showing an association of infectious agents with cancer, with various levels of involvement and either a direct or indirect causative effect, there is a scarcity of articles covering the role of

  16. Thyroid, brain and mood modulation in affective disorder: insights from molecular research and functional brain imaging.

    Science.gov (United States)

    Bauer, M; London, E D; Silverman, D H; Rasgon, N; Kirchheiner, J; Whybrow, P C

    2003-11-01

    The efficacy resulting from adjunctive use of supraphysiological doses of levothyroxine has emerged as a promising approach to therapy and prophylaxis for refractory mood disorders. Most patients with mood disorders who receive treatment with supraphysiological doses of levothyroxine have normal peripheral thyroid hormone levels, and also respond differently to the hormone and tolerate it better than healthy individuals and patients with primary thyroid diseases. Progress in molecular and functional brain imaging techniques has provided a new understanding of these phenomena, illuminating the relationship between thyroid function, mood modulation and behavior. Thyroid hormones are widely distributed in the brain and have a multitude of effects on the central nervous system. Notably many of the limbic system structures where thyroid hormone receptors are prevalent have been implicated in the pathogenesis of mood disorders. The influence of the thyroid system on neurotransmitters (particularly serotonin and norepinephrine), which putatively play a major role in the regulation of mood and behavior, may contribute to the mechanisms of mood modulation. Recent functional brain imaging studies using positron emission tomography (PET) with [ (18)F]-fluorodeoxyglucose demonstrated that thyroid hormone treatment with levothyroxine affects regional brain metabolism in patients with hypothyroidism and bipolar disorder. Theses studies confirm that thyroid hormones are active in modulating metabolic function in the mature adult brain, and provide intriging neuroanatomic clues that may guide future research.

  17. Data-driven forward model inference for EEG brain imaging

    DEFF Research Database (Denmark)

    Hansen, Sofie Therese; Hauberg, Søren; Hansen, Lars Kai

    2016-01-01

    Electroencephalography (EEG) is a flexible and accessible tool with excellent temporal resolution but with a spatial resolution hampered by volume conduction. Reconstruction of the cortical sources of measured EEG activity partly alleviates this problem and effectively turns EEG into a brain......-of-concept study, we show that, even when anatomical knowledge is unavailable, a suitable forward model can be estimated directly from the EEG. We propose a data-driven approach that provides a low-dimensional parametrization of head geometry and compartment conductivities, built using a corpus of forward models....... Combined with only a recorded EEG signal, we are able to estimate both the brain sources and a person-specific forward model by optimizing this parametrization. We thus not only solve an inverse problem, but also optimize over its specification. Our work demonstrates that personalized EEG brain imaging...

  18. A Cellular Perspective on Brain Energy Metabolism and Functional Imaging

    KAUST Repository

    Magistretti, Pierre J.

    2015-05-01

    The energy demands of the brain are high: they account for at least 20% of the body\\'s energy consumption. Evolutionary studies indicate that the emergence of higher cognitive functions in humans is associated with an increased glucose utilization and expression of energy metabolism genes. Functional brain imaging techniques such as fMRI and PET, which are widely used in human neuroscience studies, detect signals that monitor energy delivery and use in register with neuronal activity. Recent technological advances in metabolic studies with cellular resolution have afforded decisive insights into the understanding of the cellular and molecular bases of the coupling between neuronal activity and energy metabolism and pointat a key role of neuron-astrocyte metabolic interactions. This article reviews some of the most salient features emerging from recent studies and aims at providing an integration of brain energy metabolism across resolution scales. © 2015 Elsevier Inc.

  19. CARS and non-linear microscopy imaging of brain tumors

    Science.gov (United States)

    Galli, Roberta; Uckermann, Ortrud; Tamosaityte, Sandra; Geiger, Kathrin; Schackert, Gabriele; Steiner, Gerald; Koch, Edmund; Kirsch, Matthias

    2013-06-01

    Nonlinear optical microscopy offers a series of techniques that have the potential to be applied in vivo, for intraoperative identification of tumor border and in situ pathology. By addressing the different content of lipids that characterize the tumors with respect to the normal brain tissue, CARS microscopy enables to discern primary and secondary brain tumors from healthy tissue. A study performed in mouse models shows that the reduction of the CARS signal is a reliable quantity to identify brain tumors, irrespective from the tumor type. Moreover it enables to identify tumor borders and infiltrations at a cellular resolution. Integration of CARS with autogenous TPEF and SHG adds morphological and compositional details about the tissue. Examples of multimodal CARS imaging of different human tumor biopsies demonstrate the ability of the technique to retrieve information useful for histopathological diagnosis.

  20. Robust Intensity Standardization in Brain Magnetic Resonance Images.

    Science.gov (United States)

    De Nunzio, Giorgio; Cataldo, Rosella; Carlà, Alessandra

    2015-12-01

    The paper is focused on a tiSsue-Based Standardization Technique (SBST) of magnetic resonance (MR) brain images. Magnetic Resonance Imaging intensities have no fixed tissue-specific numeric meaning, even within the same MRI protocol, for the same body region, or even for images of the same patient obtained on the same scanner in different moments. This affects postprocessing tasks such as automatic segmentation or unsupervised/supervised classification methods, which strictly depend on the observed image intensities, compromising the accuracy and efficiency of many image analyses algorithms. A large number of MR images from public databases, belonging to healthy people and to patients with different degrees of neurodegenerative pathology, were employed together with synthetic MRIs. Combining both histogram and tissue-specific intensity information, a correspondence is obtained for each tissue across images. The novelty consists of computing three standardizing transformations for the three main brain tissues, for each tissue class separately. In order to create a continuous intensity mapping, spline smoothing of the overall slightly discontinuous piecewise-linear intensity transformation is performed. The robustness of the technique is assessed in a post hoc manner, by verifying that automatic segmentation of images before and after standardization gives a high overlapping (Dice index >0.9) for each tissue class, even across images coming from different sources. Furthermore, SBST efficacy is tested by evaluating if and how much it increases intertissue discrimination and by assessing gaussianity of tissue gray-level distributions before and after standardization. Some quantitative comparisons to already existing different approaches available in the literature are performed.

  1. Decoding post-stroke motor function from structural brain imaging

    Directory of Open Access Journals (Sweden)

    Jane M. Rondina

    2016-01-01

    Full Text Available Clinical research based on neuroimaging data has benefited from machine learning methods, which have the ability to provide individualized predictions and to account for the interaction among units of information in the brain. Application of machine learning in structural imaging to investigate diseases that involve brain injury presents an additional challenge, especially in conditions like stroke, due to the high variability across patients regarding characteristics of the lesions. Extracting data from anatomical images in a way that translates brain damage information into features to be used as input to learning algorithms is still an open question. One of the most common approaches to capture regional information from brain injury is to obtain the lesion load per region (i.e. the proportion of voxels in anatomical structures that are considered to be damaged. However, no systematic evaluation has yet been performed to compare this approach with using patterns of voxels (i.e. considering each voxel as a single feature. In this paper we compared both approaches applying Gaussian Process Regression to decode motor scores in 50 chronic stroke patients based solely on data derived from structural MRI. For both approaches we compared different ways to delimit anatomical areas: regions of interest from an anatomical atlas, the corticospinal tract, a mask obtained from fMRI analysis with a motor task in healthy controls and regions selected using lesion-symptom mapping. Our analysis showed that extracting features through patterns of voxels that represent lesion probability produced better results than quantifying the lesion load per region. In particular, from the different ways to delimit anatomical areas compared, the best performance was obtained with a combination of a range of cortical and subcortical motor areas as well as the corticospinal tract. These results will inform the appropriate methodology for predicting long term motor outcomes

  2. Magnetic resonance imaging using gadolinium-based contrast agents.

    Science.gov (United States)

    Mitsumori, Lee M; Bhargava, Puneet; Essig, Marco; Maki, Jeffrey H

    2014-02-01

    The purpose of this article was to review the basic properties of available gadolinium-based magnetic resonance contrast agents, discuss their fundamental differences, and explore common and evolving applications of gadolinium-based magnetic resonance contrast throughout the body excluding the central nervous system. A more specific aim of this article was to explore novel uses of these gadolinium-based contrast agents and applications where a particular agent has been demonstrated to behave differently or be better suited for certain applications than the other contrast agents in this class.

  3. BRAIN FUNCTIONAL IMAGING BASED ON BRAIN TISSUE OXYGEN CONTENT VIA MAGNETIC RESONANCE

    Directory of Open Access Journals (Sweden)

    M.A OGHABIAN

    2003-03-01

    Full Text Available Introduction: FMRI is a new approach in MRI to provide functional data of human brain activities. Some methods such as BOLD contrast, perfusion imaging, diffusion imaging, and spectroscopy in MRI have used to yield functional images. Material and Methods: This research was performed in imaging center of IMAM KHOMEINI hospital in TEHRAN in 1997. The experiments were performed on a conventional 1.5- T picker MR instrument, using a standard head coil. CE – FAST gradient echo images were obtained (TR=100, TE = 35, 128*256 matrix, 10 mm slice, FOV = 250 mm, F.A =25 Degree, NEX = 1, 13 s per image. Images were obtained during sensory - motor stimulation by pressing fingers to each other, coronal oblique images were acquired through central sulcus (precentral gyrus where the related sensory cortex is. Then, the Images were transferred to personal computers in order to eliminate noise and highlight the functional differences. These images were processed by various mathematical methods such as subtraction and student T- test. Results: Although some changes were seen in functional area, there were not significant results by the conventional system protocols. Some new protocols were designed and implemented to increase the sensitivity of the system to functional changes. Discussion: However, more research needs to be done in the future to obtain faster and more efficient techniques and in regard to clinical applications of the method.

  4. Mixture Segmentation of Multispectral MR Brain Images for Multiple Sclerosis

    Directory of Open Access Journals (Sweden)

    Lihong Li

    2005-04-01

    Full Text Available We present a fully automatic mixture model-based tissue classification of multispectral (T1- and T2-weighted magnetic resonance (MR brain images. Unlike the conventional hard classification with a unique label for each voxel, our method models a mixture to estimate the partial volumes (PV of multiple tissue types within a voxel. A new Markov random field (MRF model is proposed to reflect the spatial information of tissue mixtures. A mixture classification algorithm is performed by the maximum a posterior (MAP criterion, where the expectation maximization (EM algorithm is utilized to estimate model parameters. The algorithm interleaves segmentation with parameter estimation and improves classification in an iterative manner. The presented method is evaluated by clinical MR image datasets for quantification of brain volumes and multiple sclerosis (MS.

  5. Functional imaging of single synapses in brain slices.

    Science.gov (United States)

    Oertner, Thomas G

    2002-11-01

    The strength of synaptic connections in the brain is not fixed, but can be modulated by numerous mechanisms. Traditionally, electrophysiology has been used to characterize connections between neurons. Electrophysiology typically reports the activity of populations of synapses, while most mechanisms of plasticity are thought to operate at the level of single synapses. Recently, two-photon laser scanning microscopy has enabled us to perform optical quantal analysis of individual synapses in intact brain tissue. Here we introduce the basic principle of the two-photon microscope and discuss its main differences compared to the confocal microscope. Using calcium imaging in dendritic spines as an example, we explain the advantages of simultaneous dual-dye imaging for quantitative calcium measurements and address two common problems, dye saturation and background fluorescence subtraction.

  6. PET/SPECT imaging: From carotid vulnerability to brain viability

    Energy Technology Data Exchange (ETDEWEB)

    Meerwaldt, Robbert [Department of Surgery, Isala Clinics, Zwolle (Netherlands); Slart, Riemer H.J.A. [Department of Nuclear Medicine and Molecular Imaging, University Medical Center Groningen, Groningen (Netherlands); Dam, Gooitzen M. van [Department of Surgery, University Medical Center Groningen, Groningen (Netherlands); Luijckx, Gert-Jan [Department of Neurology, University Medical Center Groningen, Groningen (Netherlands); Tio, Rene A. [Department of Cardiology, University Medical Center Groningen, Groningen (Netherlands); Zeebregts, Clark J. [Department of Surgery, University Medical Center Groningen, Groningen (Netherlands)], E-mail: czeebregts@hotmail.com

    2010-04-15

    Background: Current key issues in ischemic stroke are related to carotid plaque vulnerability, brain viability, and timing of intervention. The treatment of ischemic stroke has evolved into urgent active interventions, as 'time is brain'. Functional imaging such as positron emission tomography (PET)/single photon emission computed tomography (SPECT) could improve selection of patients with a vulnerable plaque and evaluation of brain viability in ischemic stroke. Objective: To describe the current applications of PET and SPECT as a diagnostic tool in relation to ischemic stroke. Methods: A literature search using PubMed identified articles. Manual cross-referencing was also performed. Results: Several papers, all observational studies, identified PET/SPECT to be used as a tool to monitor systemic atheroma modifying treatment and to select high-risk patients for surgery regardless of the degree of luminal stenosis in carotid lesions. Furthermore, PET/SPECT is able to quantify the penumbra region during ischemic stroke and in this way may identify those patients who may benefit from timely intervention. Discussion: Functional imaging modalities such as PET/SPECT may become important tools for risk-assessment and evaluation of treatment strategies in carotid plaque vulnerability and brain viability. Prospective clinical studies are needed to evaluate the diagnostic accuracy of PET/SPECT.

  7. Diffusion tensor imaging of post mortem multiple sclerosis brain.

    Science.gov (United States)

    Schmierer, Klaus; Wheeler-Kingshott, Claudia A M; Boulby, Phil A; Scaravilli, Francesco; Altmann, Daniel R; Barker, Gareth J; Tofts, Paul S; Miller, David H

    2007-04-01

    Magnetic resonance imaging (MRI) is being used to probe the central nervous system (CNS) of patients with multiple sclerosis (MS), a chronic demyelinating disease. Conventional T(2)-weighted MRI (cMRI) largely fails to predict the degree of patients' disability. This shortcoming may be due to poor specificity of cMRI for clinically relevant pathology. Diffusion tensor imaging (DTI) has shown promise to be more specific for MS pathology. In this study we investigated the association between histological indices of myelin content, axonal count and gliosis, and two measures of DTI (mean diffusivity [MD] and fractional anisotropy [FA]), in unfixed post mortem MS brain using a 1.5-T MR system. Both MD and FA were significantly lower in post mortem MS brain compared to published data acquired in vivo. However, the differences of MD and FA described in vivo between white matter lesions (WMLs) and normal-appearing white matter (NAWM) were retained in this study of post mortem brain: average MD in WMLs was 0.35x10(-3) mm(2)/s (SD, 0.09) versus 0.22 (0.04) in NAWM; FA was 0.22 (0.06) in WMLs versus 0.38 (0.13) in NAWM. Correlations were detected between myelin content (Tr(myelin)) and (i) FA (r=-0.79, ppost mortem MS brain.

  8. Brain imaging of neurovascular dysfunction in Alzheimer's disease.

    Science.gov (United States)

    Montagne, Axel; Nation, Daniel A; Pa, Judy; Sweeney, Melanie D; Toga, Arthur W; Zlokovic, Berislav V

    2016-05-01

    Neurovascular dysfunction, including blood-brain barrier (BBB) breakdown and cerebral blood flow (CBF) dysregulation and reduction, are increasingly recognized to contribute to Alzheimer's disease (AD). The spatial and temporal relationships between different pathophysiological events during preclinical stages of AD, including cerebrovascular dysfunction and pathology, amyloid and tau pathology, and brain structural and functional changes remain, however, still unclear. Recent advances in neuroimaging techniques, i.e., magnetic resonance imaging (MRI) and positron emission tomography (PET), offer new possibilities to understand how the human brain works in health and disease. This includes methods to detect subtle regional changes in the cerebrovascular system integrity. Here, we focus on the neurovascular imaging techniques to evaluate regional BBB permeability (dynamic contrast-enhanced MRI), regional CBF changes (arterial spin labeling- and functional-MRI), vascular pathology (structural MRI), and cerebral metabolism (PET) in the living human brain, and examine how they can inform about neurovascular dysfunction and vascular pathophysiology in dementia and AD. Altogether, these neuroimaging approaches will continue to elucidate the spatio-temporal progression of vascular and neurodegenerative processes in dementia and AD and how they relate to each other.

  9. A technique for the deidentification of structural brain MR images

    DEFF Research Database (Denmark)

    Bischoff-Grethe, Amanda; Ozyurt, I Burak; Busa, Evelina;

    2007-01-01

    is presented, the optimal linear transform is computed for the input volume (Fischl et al. [2002]: Neuron 33:341-355; Fischl et al. [2004]: Neuroimage 23 (Suppl 1):S69-S84). A brain mask is constructed by forming the union of all voxels with nonzero probability of being brain and then morphologically dilated...... inspection showed none had brain tissue removed. In a detailed analysis of the impact of defacing on skull-stripping, 16 datasets were bias corrected with N3 (Sled et al. [1998]: IEEE Trans Med Imaging 17:87-97), defaced, and then skull-stripped using either a hybrid watershed algorithm (Ségonne et al. [2004......]: Neuroimage 22:1060-1075, in FreeSurfer) or Brain Surface Extractor (Sandor and Leahy [1997]: IEEE Trans Med Imaging 16:41-54; Shattuck et al. [2001]: Neuroimage 13:856-876); defacing did not appreciably influence the outcome of skull-stripping. Results suggested that the automatic defacing algorithm...

  10. Label-free dopamine imaging in live rat brain slices.

    Science.gov (United States)

    Sarkar, Bidyut; Banerjee, Arkarup; Das, Anand Kant; Nag, Suman; Kaushalya, Sanjeev Kumar; Tripathy, Umakanta; Shameem, Mohammad; Shukla, Shubha; Maiti, Sudipta

    2014-05-21

    Dopaminergic neurotransmission has been investigated extensively, yet direct optical probing of dopamine has not been possible in live cells. Here we image intracellular dopamine with sub-micrometer three-dimensional resolution by harnessing its intrinsic mid-ultraviolet (UV) autofluorescence. Two-photon excitation with visible light (540 nm) in conjunction with a non-epifluorescent detection scheme is used to circumvent the UV toxicity and the UV transmission problems. The method is established by imaging dopamine in a dopaminergic cell line and in control cells (glia), and is validated by mass spectrometry. We further show that individual dopamine vesicles/vesicular clusters can be imaged in cultured rat brain slices, thereby providing a direct visualization of the intracellular events preceding dopamine release induced by depolarization or amphetamine exposure. Our technique opens up a previously inaccessible mid-ultraviolet spectral regime (excitation ~270 nm, emission free imaging of native molecules in live tissue.

  11. PANDA: a pipeline toolbox for analyzing brain diffusion images

    Directory of Open Access Journals (Sweden)

    Zaixu eCui

    2013-02-01

    Full Text Available Diffusion magnetic resonance imaging (dMRI is widely used in both scientific research and clinical practice in in-vivo studies of the human brain. While a number of post-processing packages have been developed, fully automated processing of dMRI datasets remains challenging. Here, we developed a MATLAB toolbox named Pipeline for Analyzing braiN Diffusion imAges (PANDA for fully automated processing of brain diffusion images. The processing modules of a few established packages, including FMRIB Software Library (FSL, Pipeline System for Octave and Matlab (PSOM, Diffusion Toolkit and MRIcron, were employed in PANDA. Using any number of raw dMRI datasets from different subjects, in either DICOM or NIfTI format, PANDA can automatically perform a series of steps to process DICOM/NIfTI to diffusion metrics (e.g., FA and MD that are ready for statistical analysis at the voxel-level, the atlas-level and the Tract-Based Spatial Statistics (TBSS-level and can finish the construction of anatomical brain networks for all subjects. In particular, PANDA can process different subjects in parallel, using multiple cores either in a single computer or in a distributed computing environment, thus greatly reducing the time cost when dealing with a large number of datasets. In addition, PANDA has a friendly graphical user interface (GUI, allowing the user to be interactive and to adjust the input/output settings, as well as the processing parameters. As an open-source package, PANDA is freely available at http://www.nitrc.org/projects/panda/. This novel toolbox is expected to substantially simplify the image processing of dMRI datasets and facilitate human structural connectome studies.

  12. PANDA: a pipeline toolbox for analyzing brain diffusion images.

    Science.gov (United States)

    Cui, Zaixu; Zhong, Suyu; Xu, Pengfei; He, Yong; Gong, Gaolang

    2013-01-01

    Diffusion magnetic resonance imaging (dMRI) is widely used in both scientific research and clinical practice in in-vivo studies of the human brain. While a number of post-processing packages have been developed, fully automated processing of dMRI datasets remains challenging. Here, we developed a MATLAB toolbox named "Pipeline for Analyzing braiN Diffusion imAges" (PANDA) for fully automated processing of brain diffusion images. The processing modules of a few established packages, including FMRIB Software Library (FSL), Pipeline System for Octave and Matlab (PSOM), Diffusion Toolkit and MRIcron, were employed in PANDA. Using any number of raw dMRI datasets from different subjects, in either DICOM or NIfTI format, PANDA can automatically perform a series of steps to process DICOM/NIfTI to diffusion metrics [e.g., fractional anisotropy (FA) and mean diffusivity (MD)] that are ready for statistical analysis at the voxel-level, the atlas-level and the Tract-Based Spatial Statistics (TBSS)-level and can finish the construction of anatomical brain networks for all subjects. In particular, PANDA can process different subjects in parallel, using multiple cores either in a single computer or in a distributed computing environment, thus greatly reducing the time cost when dealing with a large number of datasets. In addition, PANDA has a friendly graphical user interface (GUI), allowing the user to be interactive and to adjust the input/output settings, as well as the processing parameters. As an open-source package, PANDA is freely available at http://www.nitrc.org/projects/panda/. This novel toolbox is expected to substantially simplify the image processing of dMRI datasets and facilitate human structural connectome studies.

  13. Parkinson’s Disease Biomarkers Program Brain Imaging Repository

    OpenAIRE

    Ofori, Edward; Du, Guangwei; Babcock, Debra; Huang, Xuemei; Vaillancourt, David E.

    2015-01-01

    The Parkinson’s Disease Biomarkers Program (PDBP) is a multi-site study designed to identify Parkinson’s Disease (PD) biomarkers that can be used to improve the understanding of PD pathophysiology and to develop tools that provide novel measures to evaluate PD clinical trials. The PDBP consortium comprises numerous individual projects of which two are specifically geared to the development of brain imaging markers for diagnosis, progression, and prognosis of PD or related disorders. All study...

  14. Diffusion MR Imaging of the Brain in Patients with Cancer

    Directory of Open Access Journals (Sweden)

    J. Matthew Debnam

    2011-01-01

    Full Text Available Over the last several years, there has been significant advancement in the molecular characterization of intracranial diseases, particularly cerebral neoplasms. While nuclear medicine technology, including PET/CT, has been at the foreground of exploration, new MR imaging techniques, specifically diffusion-weighted and diffusion tensor imaging, have shown interesting applications towards advancing our understanding of cancer involving the brain. In this paper, we review the fundamentals and basic physics of these techniques, and their applications to patient care for both general diagnostic use and in answering specific questions in selection of patients in terms of expected response to treatment.

  15. In Vivo Photoacoustic Imaging of Prostate Cancer Using Targeted Contrast Agent

    Science.gov (United States)

    2015-09-01

    AD______________ AWARD NUMBER: W81XWH-14-1-0242 TITLE: In Vivo Photoacoustic Imaging of Prostate Cancer Using Targeted Contrast Agent...2015 4. TITLE AND SUBTITLE In Vivo Photoacoustic Imaging of Prostate Cancer Using Targeted Contrast Agent 5a. CONTRACT NUMBER W81XWH-14-1-0242 5b...men with false positive PSA elevation and to ensure successful biopsy for those with small cancers. Photoacoustic imaging is an emerging functional

  16. Simultaneous MRI and PET imaging of a rat brain

    Science.gov (United States)

    Raylman, Raymond R.; Majewski, Stan; Lemieux, Susan K.; Sendhil Velan, S.; Kross, Brian; Popov, Vladimir; Smith, Mark F.; Weisenberger, Andrew G.; Zorn, Carl; Marano, Gary D.

    2006-12-01

    Multi-modality imaging is rapidly becoming a valuable tool in the diagnosis of disease and in the development of new drugs. Functional images produced with PET fused with anatomical structure images created by MRI will allow the correlation of form with function. Our group is developing a system to acquire MRI and PET images contemporaneously. The prototype device consists of two opposed detector heads, operating in coincidence mode. Each MRI-PET detector module consists of an array of LSO detector elements coupled through a long fibre optic light guide to a single Hamamatsu flat panel position-sensitive photomultiplier tube (PSPMT). The use of light guides allows the PSPMTs to be positioned outside the bore of a 3T MRI scanner where the magnetic field is relatively small. To test the device, simultaneous MRI and PET images of the brain of a male Sprague Dawley rat injected with FDG were successfully obtained. The images revealed no noticeable artefacts in either image set. Future work includes the construction of a full ring PET scanner, improved light guides and construction of a specialized MRI coil to permit higher quality MRI imaging.

  17. Simultaneous MRI and PET imaging of a rat brain

    Energy Technology Data Exchange (ETDEWEB)

    Raylman, Raymond R [Center for Advanced Imaging, Department of Radiology, Box 9236, West Virginia University, Morgantown, WV (United States); Majewski, Stan [Thomas Jefferson National Accelerator Facility, 12000 Jefferson Ave., Newport News, VA (United States); Lemieux, Susan K [Center for Advanced Imaging, Department of Radiology, Box 9236, West Virginia University, Morgantown, WV (United States); Velan, S Sendhil [Center for Advanced Imaging, Department of Radiology, Box 9236, West Virginia University, Morgantown, WV (United States); Kross, Brian [Thomas Jefferson National Accelerator Facility, 12000 Jefferson Ave., Newport News, VA (United States); Popov, Vladimir [Thomas Jefferson National Accelerator Facility, 12000 Jefferson Ave., Newport News, VA (United States); Smith, Mark F [Thomas Jefferson National Accelerator Facility, 12000 Jefferson Ave., Newport News, VA (United States); Weisenberger, Andrew G [Thomas Jefferson National Accelerator Facility, 12000 Jefferson Ave., Newport News, VA (United States); Zorn, Carl [Thomas Jefferson National Accelerator Facility, 12000 Jefferson Ave., Newport News, VA (United States); Marano, Gary D [Center for Advanced Imaging, Department of Radiology, Box 9236, West Virginia University, Morgantown, WV (United States)

    2006-12-21

    Multi-modality imaging is rapidly becoming a valuable tool in the diagnosis of disease and in the development of new drugs. Functional images produced with PET fused with anatomical structure images created by MRI will allow the correlation of form with function. Our group is developing a system to acquire MRI and PET images contemporaneously. The prototype device consists of two opposed detector heads, operating in coincidence mode. Each MRI-PET detector module consists of an array of LSO detector elements coupled through a long fibre optic light guide to a single Hamamatsu flat panel position-sensitive photomultiplier tube (PSPMT). The use of light guides allows the PSPMTs to be positioned outside the bore of a 3T MRI scanner where the magnetic field is relatively small. To test the device, simultaneous MRI and PET images of the brain of a male Sprague Dawley rat injected with FDG were successfully obtained. The images revealed no noticeable artefacts in either image set. Future work includes the construction of a full ring PET scanner, improved light guides and construction of a specialized MRI coil to permit higher quality MRI imaging.

  18. Ant Colony Clustering Algorithm and Improved Markov Random Fusion Algorithm in Image Segmentation of Brain Images

    Directory of Open Access Journals (Sweden)

    Guohua Zou

    2016-12-01

    Full Text Available New medical imaging technology, such as Computed Tomography and Magnetic Resonance Imaging (MRI, has been widely used in all aspects of medical diagnosis. The purpose of these imaging techniques is to obtain various qualitative and quantitative data of the patient comprehensively and accurately, and provide correct digital information for diagnosis, treatment planning and evaluation after surgery. MR has a good imaging diagnostic advantage for brain diseases. However, as the requirements of the brain image definition and quantitative analysis are always increasing, it is necessary to have better segmentation of MR brain images. The FCM (Fuzzy C-means algorithm is widely applied in image segmentation, but it has some shortcomings, such as long computation time and poor anti-noise capability. In this paper, firstly, the Ant Colony algorithm is used to determine the cluster centers and the number of FCM algorithm so as to improve its running speed. Then an improved Markov random field model is used to improve the algorithm, so that its antinoise ability can be improved. Experimental results show that the algorithm put forward in this paper has obvious advantages in image segmentation speed and segmentation effect.

  19. Imaging of non tumorous and tumorous human brain tissue with full-field optical coherence tomography

    CERN Document Server

    Assayag, Osnath; Devaux, Bertrand; Harms, Fabrice; Pallud, Johan; Chretien, Fabrice; Boccara, Claude; Varlet, Pascale

    2013-01-01

    A prospective study was performed on neurosurgical samples from 18 patients to evaluate the use of Full-Field Optical Coherence Tomography (FF-OCT) in brain tumor diagnosis. FF-OCT captures en face slices of tissue samples at 1\\mum resolution in 3D with a typical 200\\mum imaging depth. A 1cm2 specimen is scanned at a single depth and processed in about 5 minutes. This rapid imaging process is non-invasive and 30 requires neither contrast agent injection nor tissue preparation, which makes it particularly well suited to medical imaging applications. Temporal chronic epileptic parenchyma and brain tumors such as meningiomas, low- grade and high-grade gliomas, and choroid plexus papilloma were imaged. A subpopulation of neurons, myelin fibers and CNS vasculature were clearly identified. Cortex could be discriminated from white matter, but individual glial cells as astrocytes (normal or reactive) or oligodendrocytes were not observable. This study reports for the first time on the feasibility of using FF-OCT in a...

  20. Molecular Imaging of the Brain Using Multi-Quantum Coherence and Diagnostics of Brain Disorders

    CERN Document Server

    Kaila, M M

    2013-01-01

    This book examines multi-quantum magnetic resonance imaging methods and the diagnostics of brain disorders. It consists of two Parts. The part I is initially devoted towards the basic concepts of the conventional single quantum MRI techniques. It is supplemented by the basic knowledge required to understand multi-quantum MRI. Practical illustrations are included both on recent developments in conventional MRI and the MQ-MRI. This is to illustrate the connection between theoretical concepts and their scope in the clinical applications. The Part II initially sets out the basic details about quadrupole charge distribution present in certain nuclei and their importance about the functions they perform in our brain. Some simplified final mathematical expressions are included to illustrate facts about the basic concepts of the quantum level interactions between magnetic dipole and the electric quadrupole behavior of useful nuclei present in the brain. Selected practical illustrations, from research and clinical pra...

  1. Comparative assessments of the effects of alcohol exposure on fetal brain development using optical coherence tomography and ultrasound imaging

    Science.gov (United States)

    Sudheendran, Narendran; Bake, Shameena; Miranda, Rajesh C.; Larin, Kirill V.

    2013-02-01

    The developing fetal brain is vulnerable to a variety of environmental agents including maternal ethanol consumption. Preclinical studies on the development and amelioration of fetal teratology would be significantly facilitated by the application of high resolution imaging technologies like optical coherence tomography (OCT) and high-frequency ultrasound (US). This study investigates the ability of these imaging technologies to measure the effects of maternal ethanol exposure on brain development, ex vivo, in fetal mice. Pregnant mice at gestational day 12.5 were administered ethanol (3 g/Kg b.wt.) or water by intragastric gavage, twice daily for three consecutive days. On gestational day 14.5, fetuses were collected and imaged. Three-dimensional images of the mice fetus brains were obtained by OCT and high-resolution US, and the volumes of the left and right ventricles of the brain were measured. Ethanol-exposed fetuses exhibited a statistically significant, 2-fold increase in average left and right ventricular volumes compared with the ventricular volume of control fetuses, with OCT-derived measures of 0.38 and 0.18 mm3, respectively, whereas the boundaries of the fetal mouse lateral ventricles were not clearly definable with US imaging. Our results indicate that OCT is a useful technology for assessing ventriculomegaly accompanying alcohol-induced developmental delay. This study clearly demonstrated advantages of using OCT for quantitative assessment of embryonic development compared with US imaging.

  2. Image segmentation by EM-based adaptive pulse coupled neural networks in brain magnetic resonance imaging.

    Science.gov (United States)

    Fu, J C; Chen, C C; Chai, J W; Wong, S T C; Li, I C

    2010-06-01

    We propose an automatic hybrid image segmentation model that integrates the statistical expectation maximization (EM) model and the spatial pulse coupled neural network (PCNN) for brain magnetic resonance imaging (MRI) segmentation. In addition, an adaptive mechanism is developed to fine tune the PCNN parameters. The EM model serves two functions: evaluation of the PCNN image segmentation and adaptive adjustment of the PCNN parameters for optimal segmentation. To evaluate the performance of the adaptive EM-PCNN, we use it to segment MR brain image into gray matter (GM), white matter (WM) and cerebrospinal fluid (CSF). The performance of the adaptive EM-PCNN is compared with that of the non-adaptive EM-PCNN, EM, and Bias Corrected Fuzzy C-Means (BCFCM) algorithms. The result is four sets of boundaries for the GM and the brain parenchyma (GM+WM), the two regions of most interest in medical research and clinical applications. Each set of boundaries is compared with the golden standard to evaluate the segmentation performance. The adaptive EM-PCNN significantly outperforms the non-adaptive EM-PCNN, EM, and BCFCM algorithms in gray mater segmentation. In brain parenchyma segmentation, the adaptive EM-PCNN significantly outperforms the BCFCM only. However, the adaptive EM-PCNN is better than the non-adaptive EM-PCNN and EM on average. We conclude that of the three approaches, the adaptive EM-PCNN yields the best results for gray matter and brain parenchyma segmentation.

  3. Magnetic resonance imaging of regional hemodynamic and cerebrovascular recovery after lateral fluid-percussion brain injury in rats

    OpenAIRE

    2010-01-01

    Hemodynamic and cerebrovascular factors are crucially involved in secondary damage after traumatic brain injury (TBI). With magnetic resonance imaging, this study aimed to quantify regional cerebral blood flow (CBF) by arterial spin labeling and cerebral blood volume by using an intravascular contrast agent, during 14 days after lateral fluid-percussion injury (LFPI) in rats. Immunohistochemical analysis of vessel density was used to evaluate the contribution of vascular damage. Results show ...

  4. Pitfalls and Limitations of PET/CT in Brain Imaging.

    Science.gov (United States)

    Salmon, Eric; Bernard Ir, Claire; Hustinx, Roland

    2015-11-01

    Neurologic applications were at the forefront of PET imaging when the technique was developed in the mid-1970s. Although oncologic indications have become prominent in terms of number of studies performed worldwide, neurology remains a major field in which functional imaging provides unique information, both for clinical and research purposes. The evaluation of glucose metabolism using FDG remains the most frequent exploration, but in recent years, alternative radiotracers have been developed, including fluorinated amino acid analogues for primary brain tumor imaging and fluorinated compounds for assessing the amyloid deposits in patients with suspected Alzheimer disease. As the brain is enclosed in the skull, which presents fixed landmarks, it is relatively easy to coregister images obtained with various cross-sectional imaging methods, either functional or anatomical, with a relatively high accuracy and robustness. Nevertheless, PET in neurology has fully benefited from the advent of hybrid imaging. Attenuation and scatter correction is now much faster and equally accurate, using CT as compared with the traditional transmission scan using an external radioactive source. The perfect coregistration with the CT data, which is now systematically performed, also provides its own set of valuable information, for instance regarding cerebral atrophy. However, hybrid imaging in neurology comes with pitfalls and limitations, in addition to those that are well known, for example, blood glucose levels or psychotropic drugs that greatly affect the physiological FDG uptake. Movements of the patient's head, either during the PET acquisition or between the PET and the CT acquisitions will generate artifacts that may be very subtle yet lead to erroneous interpretation of the study. Similarly, quantitative analysis, such as voxel-based analyses, may prove very helpful in improving the diagnostic accuracy and the reproducibility of the reading, but a wide variety of artifacts may

  5. [Molecular imaging of histamine receptors in the human brain].

    Science.gov (United States)

    Tashiro, Manabu; Yanai, Kazuhiko

    2007-03-01

    Brain histamine is involved in a wide range of physiological functions such as regulation of sleep-wake cycle, arousal, appetite control, cognition, learning and memory mainly through the 4 receptor subtypes: H1, H2, H3 and H4. Neurons producing histamine, histaminergic neurons, are exclusively located in the tuberomammillary nucleus of the posterior hypothalamus and are transmitting histamine to almost all regions of the brain. Roles of brain histamine have been studied using animals including knock-out mice and human subjects. For clinical studies, molecular imaging technique such as positron emission tomography (PET), with ligands such as [11C]doxepin and [11C]pyrilamine, has been a useful tool. A series of clinical studies on histamine H1 antagonists, or antihistamines, have demonstrated that antihistamines can be classified into sedative, mildly-sedative and non-sedative drugs according to their blood-brain barrier (BBB) permeability, showing apparent clinical usefulness regarding QOL, work efficiency and traffic safety of allergic patients. PET has also been used for elucidation of aging effects and pathophysiological roles of histaminergic nervous system in various neuropsychiatric disorders such as Alzheimer's disease, schizophrenia and depression, where H1 receptor binding potentials were lower than age-matched healthy controls. It has been also demonstrated that brain histamine functions as an endogenous anti-epileptic. In addition, H3 receptors are located in the presynaptic sites of not only histaminergic nerves but also in other nervous systems such as serotonergic, cholinergic and dopaminergic systems, and to be regulating secretion of various neurotransmitters. Nowadays, H3 receptors have been thought to be a new target of drug treatment of various neuropsychiatric disorders. There are still many research topics to be investigated regarding molecular imaging of histamine and histamine receptors. The authors hope that this line of research contributes

  6. Brain imaging in the assessment for epilepsy surgery.

    Science.gov (United States)

    Duncan, John S; Winston, Gavin P; Koepp, Matthias J; Ourselin, Sebastien

    2016-04-01

    Brain imaging has a crucial role in the presurgical assessment of patients with epilepsy. Structural imaging reveals most cerebral lesions underlying focal epilepsy. Advances in MRI acquisitions including diffusion-weighted imaging, post-acquisition image processing techniques, and quantification of imaging data are increasing the accuracy of lesion detection. Functional MRI can be used to identify areas of the cortex that are essential for language, motor function, and memory, and tractography can reveal white matter tracts that are vital for these functions, thus reducing the risk of epilepsy surgery causing new morbidities. PET, SPECT, simultaneous EEG and functional MRI, and electrical and magnetic source imaging can be used to infer the localisation of epileptic foci and assist in the design of intracranial EEG recording strategies. Progress in semi-automated methods to register imaging data into a common space is enabling the creation of multimodal three-dimensional patient-specific datasets. These techniques show promise for the demonstration of the complex relations between normal and abnormal structural and functional data and could be used to direct precise intracranial navigation and surgery for individual patients.

  7. The dynamic dielectric at a brain functional site and an EM wave approach to functional brain imaging.

    Science.gov (United States)

    Li, X P; Xia, Q; Qu, D; Wu, T C; Yang, D G; Hao, W D; Jiang, X; Li, X M

    2014-11-04

    Functional brain imaging has tremendous applications. The existing methods for functional brain imaging include functional Magnetic Resonant Imaging (fMRI), scalp electroencephalography (EEG), implanted EEG, magnetoencephalography (MEG) and Positron Emission Tomography (PET), which have been widely and successfully applied to various brain imaging studies. To develop a new method for functional brain imaging, here we show that the dielectric at a brain functional site has a dynamic nature, varying with local neuronal activation as the permittivity of the dielectric varies with the ion concentration of the extracellular fluid surrounding neurons in activation. Therefore, the neuronal activation can be sensed by a radiofrequency (RF) electromagnetic (EM) wave propagating through the site as the phase change of the EM wave varies with the permittivity. Such a dynamic nature of the dielectric at a brain functional site provides the basis for an RF EM wave approach to detecting and imaging neuronal activation at brain functional sites, leading to an RF EM wave approach to functional brain imaging.

  8. Automated delineation of stroke lesions using brain CT images

    Directory of Open Access Journals (Sweden)

    Céline R. Gillebert

    2014-01-01

    Full Text Available Computed tomographic (CT images are widely used for the identification of abnormal brain tissue following infarct and hemorrhage in stroke. Manual lesion delineation is currently the standard approach, but is both time-consuming and operator-dependent. To address these issues, we present a method that can automatically delineate infarct and hemorrhage in stroke CT images. The key elements of this method are the accurate normalization of CT images from stroke patients into template space and the subsequent voxelwise comparison with a group of control CT images for defining areas with hypo- or hyper-intense signals. Our validation, using simulated and actual lesions, shows that our approach is effective in reconstructing lesions resulting from both infarct and hemorrhage and yields lesion maps spatially consistent with those produced manually by expert operators. A limitation is that, relative to manual delineation, there is reduced sensitivity of the automated method in regions close to the ventricles and the brain contours. However, the automated method presents a number of benefits in terms of offering significant time savings and the elimination of the inter-operator differences inherent to manual tracing approaches. These factors are relevant for the creation of large-scale lesion databases for neuropsychological research. The automated delineation of stroke lesions from CT scans may also enable longitudinal studies to quantify changes in damaged tissue in an objective and reproducible manner.

  9. Registration of multimodal brain images: some experimental results

    Science.gov (United States)

    Chen, Hua-mei; Varshney, Pramod K.

    2002-03-01

    Joint histogram of two images is required to uniquely determine the mutual information between the two images. It has been pointed out that, under certain conditions, existing joint histogram estimation algorithms like partial volume interpolation (PVI) and linear interpolation may result in different types of artifact patterns in the MI based registration function by introducing spurious maxima. As a result, the artifacts may hamper the global optimization process and limit registration accuracy. In this paper we present an extensive study of interpolation-induced artifacts using simulated brain images and show that similar artifact patterns also exist when other intensity interpolation algorithms like cubic convolution interpolation and cubic B-spline interpolation are used. A new joint histogram estimation scheme named generalized partial volume estimation (GPVE) is proposed to eliminate the artifacts. A kernel function is involved in the proposed scheme and when the 1st order B-spline is chosen as the kernel function, it is equivalent to the PVI. A clinical brain image database furnished by Vanderbilt University is used to compare the accuracy of our algorithm with that of PVI. Our experimental results show that the use of higher order kernels can effectively remove the artifacts and, in cases when MI based registration result suffers from the artifacts, registration accuracy can be improved significantly.

  10. Ultrasound contrast agent imaging: Real-time imaging of the superharmonics

    Energy Technology Data Exchange (ETDEWEB)

    Peruzzini, D.; Viti, J. [MSD lab, Department of Information Engineering, Univ of Florence, Via S.Marta, 3, 50139 Firenze (Italy); Erasmus MC, ’s-Gravendijkwal 230, Faculty Building, Ee 2302, 3015 CE Rotterdam (Netherlands); Tortoli, P. [MSD lab, Department of Information Engineering, Univ of Florence, Via S.Marta, 3, 50139 Firenze (Italy); Verweij, M. D. [Acoustical Wavefield Imaging, ImPhys, Delft Univ Technology, van der Waalsweg 8, 2628 CH Delft (Netherlands); Jong, N. de; Vos, H. J., E-mail: h.vos@erasmusmc.nl [Erasmus MC, ’s-Gravendijkwal 230, Faculty Building, Ee 2302, 3015 CE Rotterdam (Netherlands); Acoustical Wavefield Imaging, ImPhys, Delft Univ Technology, van der Waalsweg 8, 2628 CH Delft (Netherlands)

    2015-10-28

    Currently, in medical ultrasound contrast agent (UCA) imaging the second harmonic scattering of the microbubbles is regularly used. This scattering is in competition with the signal that is caused by nonlinear wave propagation in tissue. It was reported that UCA imaging based on the third or higher harmonics, i.e. “superharmonic” imaging, shows better contrast. However, the superharmonic scattering has a lower signal level compared to e.g. second harmonic signals. This study investigates the contrast-to-tissue ratio (CTR) and signal to noise ratio (SNR) of superharmonic UCA scattering in a tissue/vessel mimicking phantom using a real-time clinical scanner. Numerical simulations were performed to estimate the level of harmonics generated by the microbubbles. Data were acquired with a custom built dual-frequency cardiac phased array probe. Fundamental real-time images were produced while beam formed radiofrequency (RF) data was stored for further offline processing. The phantom consisted of a cavity filled with UCA surrounded by tissue mimicking material. The acoustic pressure in the cavity of the phantom was 110 kPa (MI = 0.11) ensuring non-destructivity of UCA. After processing of the acquired data from the phantom, the UCA-filled cavity could be clearly observed in the images, while tissue signals were suppressed at or below the noise floor. The measured CTR values were 36 dB, >38 dB, and >32 dB, for the second, third, and fourth harmonic respectively, which were in agreement with those reported earlier for preliminary contrast superharmonic imaging. The single frame SNR values (in which ‘signal’ denotes the signal level from the UCA area) were 23 dB, 18 dB, and 11 dB, respectively. This indicates that noise, and not the tissue signal, is the limiting factor for the UCA detection when using the superharmonics in nondestructive mode.

  11. Ultrasound contrast agent imaging: Real-time imaging of the superharmonics

    Science.gov (United States)

    Peruzzini, D.; Viti, J.; Tortoli, P.; Verweij, M. D.; de Jong, N.; Vos, H. J.

    2015-10-01

    Currently, in medical ultrasound contrast agent (UCA) imaging the second harmonic scattering of the microbubbles is regularly used. This scattering is in competition with the signal that is caused by nonlinear wave propagation in tissue. It was reported that UCA imaging based on the third or higher harmonics, i.e. "superharmonic" imaging, shows better contrast. However, the superharmonic scattering has a lower signal level compared to e.g. second harmonic signals. This study investigates the contrast-to-tissue ratio (CTR) and signal to noise ratio (SNR) of superharmonic UCA scattering in a tissue/vessel mimicking phantom using a real-time clinical scanner. Numerical simulations were performed to estimate the level of harmonics generated by the microbubbles. Data were acquired with a custom built dual-frequency cardiac phased array probe. Fundamental real-time images were produced while beam formed radiofrequency (RF) data was stored for further offline processing. The phantom consisted of a cavity filled with UCA surrounded by tissue mimicking material. The acoustic pressure in the cavity of the phantom was 110 kPa (MI = 0.11) ensuring non-destructivity of UCA. After processing of the acquired data from the phantom, the UCA-filled cavity could be clearly observed in the images, while tissue signals were suppressed at or below the noise floor. The measured CTR values were 36 dB, >38 dB, and >32 dB, for the second, third, and fourth harmonic respectively, which were in agreement with those reported earlier for preliminary contrast superharmonic imaging. The single frame SNR values (in which `signal' denotes the signal level from the UCA area) were 23 dB, 18 dB, and 11 dB, respectively. This indicates that noise, and not the tissue signal, is the limiting factor for the UCA detection when using the superharmonics in nondestructive mode.

  12. Connecting combat-related mild traumatic brain injury with posttraumatic stress disorder symptoms through brain imaging.

    Science.gov (United States)

    Costanzo, Michelle E; Chou, Yi-Yu; Leaman, Suzanne; Pham, Dzung L; Keyser, David; Nathan, Dominic E; Coughlin, Mary; Rapp, Paul; Roy, Michael J

    2014-08-01

    Mild traumatic brain injury (mTBI) and posttraumatic stress disorder (PTSD) may share common symptom and neuropsychological profiles in military service members (SMs) following deployment; while a connection between the two conditions is plausible, the relationship between them has been difficult to discern. The intent of this report is to enhance our understanding of the relationship between findings on structural and functional brain imaging and symptoms of PTSD. Within a cohort of SMs who did not meet criteria for PTSD but were willing to complete a comprehensive assessment within 2 months of their return from combat deployment, we conducted a nested case-control analysis comparing those with combat-related mTBI to age/gender-matched controls with diffusion tensor imaging, resting state functional magnetic resonance imaging and a range of psychological measures. We report degraded white matter integrity in those with a history of combat mTBI, and a positive correlation between the white matter microstructure and default mode network (DMN) connectivity. Higher clinician-administered and self-reported subthreshold PTSD symptoms were reported in those with combat mTBI. Our findings offer a potential mechanism through which mTBI may alter brain function, and in turn, contribute to PTSD symptoms.

  13. Hybrid material as contrast agent in magnetic resonance images

    OpenAIRE

    Botella Asunción, Pablo; Cabrera García, Alejandro

    2015-01-01

    [EN] The invention relates to a contrast agent of magnetic resonance based on a hybrid material formed by an organo-metallic core derived from Prussian blue and a silica cover, and optionally, molecules of a poly(ethylene glycol), a fluorescent agent, a radio nucleus and/or a substance that directs to specific receptors, cells or tissues, joined by covalent bonding to the surface of the inorganic cover.

  14. Ultrasound Delivery of an Anti-Aβ Therapeutic Agent to the Brain in a Mouse Model of Alzheimer's Disease

    Science.gov (United States)

    Jordão, Jessica F.; Ayala-Grosso, Carlos A.; Chopra, Rajiv; McLaurin, JoAnne; Aubert, Isabelle; Hynynen, Kullervo

    2009-04-01

    Plaques composed of amyloid-beta (Aβ) peptides represent a pathological hallmark in the brain of patients with Alzheimer's disease. Aβ oligomers are considered cytotoxic and several therapeutic approaches focus on reducing Aβ load in the brain of Alzheimer's patients. The efficacy of most anti-Aβ agents is significantly limited because they do not cross the blood-brain-barrier. Innovative technologies capable of enhancing the permeability of the blood-brain barrier, thereby allowing entry of therapeutic agents into the brain, show great promise in circumventing this problem. The application of low-intensity focused ultrasound in the presence of an ultrasound contrast agent causes localized and transient permeability of the blood-brain barrier. We demonstrate the value of this technology for the delivery of anti-Aβ antibodies to the brain of TgCRND8 mice, a mouse model of Alzheimer's disease exhibiting Aβ plaques. BAM-10, an anti-Aβ antibody, was injected into the tail vein simultaneously with exposure to MRI-guided, low-intensity focused ultrasound (FUS) to one hemisphere of TgCNRD8 mice. Four hours after treatment, antibodies were detected at significant amounts only in the brain of mice receiving FUS in addition to BAM-10. This data provides a proof-of-concept that FUS allows anti-Aβ therapeutics to efficiently enter the brain and target Aβ plaques. Four days following a single treatment with BAM-10 and MRI-guided FUS, a significant decrease in the number of Aβ plaques on the side of the treated hemisphere was observed in TgCRND8 mice. In conclusion low-intensity, focused ultrasound is effective in delivering Aβ antibodies to the brain. This technology has the potential to enhance current anti-Aβ treatments by allowing increased exposure of amyloid plaques to treatment agents.

  15. The Multimodal Brain Tumor Image Segmentation Benchmark (BRATS)

    DEFF Research Database (Denmark)

    Menze, Bjoern H.; Jakab, Andras; Bauer, Stefan

    2015-01-01

    In this paper we report the set-up and results of the Multimodal Brain Tumor Image Segmentation Benchmark (BRATS) organized in conjunction with the MICCAI 2012 and 2013 conferences. Twenty state-of-the-art tumor segmentation algorithms were applied to a set of 65 multi-contrast MR scans of low......- and high-grade glioma patients – manually annotated by up to four raters – and to 65 comparable scans generated using tumor image simulation software. Quantitative evaluations revealed considerable disagreement between the human raters in segmenting various tumor sub-regions (Dice scores in the range 74...... a hierarchical majority vote yielded segmentations that consistently ranked above all individual algorithms, indicating remaining opportunities for further methodological improvements. The BRATS image data and manual annotations continue to be publicly available through an online evaluation system as an ongoing...

  16. A technique for the deidentification of structural brain MR images

    DEFF Research Database (Denmark)

    Bischoff-Grethe, Amanda; Ozyurt, I Burak; Busa, Evelina;

    2007-01-01

    Due to the increasing need for subject privacy, the ability to deidentify structural MR images so that they do not provide full facial detail is desirable. A program was developed that uses models of nonbrain structures for removing potentially identifying facial features. When a novel image....... All voxels outside the mask with a nonzero probability of being a facial feature are set to 0. The algorithm was applied to 342 datasets that included two different T1-weighted pulse sequences and four different diagnoses (depressed, Alzheimer's, and elderly and young control groups). Visual...... inspection showed none had brain tissue removed. In a detailed analysis of the impact of defacing on skull-stripping, 16 datasets were bias corrected with N3 (Sled et al. [1998]: IEEE Trans Med Imaging 17:87-97), defaced, and then skull-stripped using either a hybrid watershed algorithm (Ségonne et al. [2004...

  17. Imaging of sodium in the brain: a brief review.

    Science.gov (United States)

    Shah, N Jon; Worthoff, Wieland A; Langen, Karl-Josef

    2016-02-01

    Sodium-based MRI plays a vital role in the study of metabolism and can unveil valuable information about emerging and existing pathology--in particular in the human brain. Sodium is the second most abundant MR active nucleus in living tissue and, due to its quadrupolar nature, has magnetic properties not common to conventional proton MRI, which can reveal further insights, such as information on the compartmental distribution of intra- and extracellular sodium. Nevertheless, the use of sodium nuclei for imaging comes at the expense of a lower sensitivity and significantly reduced relaxation times, making in vivo sodium studies feasible only at high magnetic field strength and by the use of dedicated pulse sequences. Hybrid imaging combining sodium MRI and positron emission tomography (PET) simultaneously is a novel and promising approach to access information on dynamic metabolism with much increased, PET-derived specificity. Application of this new methodology is demonstrated herein using examples from tumour imaging.

  18. Data-driven forward model inference for EEG brain imaging.

    Science.gov (United States)

    Hansen, Sofie Therese; Hauberg, Søren; Hansen, Lars Kai

    2016-06-13

    Electroencephalography (EEG) is a flexible and accessible tool with excellent temporal resolution but with a spatial resolution hampered by volume conduction. Reconstruction of the cortical sources of measured EEG activity partly alleviates this problem and effectively turns EEG into a brain imaging device. The quality of the source reconstruction depends on the forward model which details head geometry and conductivities of different head compartments. These person-specific factors are complex to determine, requiring detailed knowledge of the subject's anatomy and physiology. In this proof-of-concept study, we show that, even when anatomical knowledge is unavailable, a suitable forward model can be estimated directly from the EEG. We propose a data-driven approach that provides a low-dimensional parametrization of head geometry and compartment conductivities, built using a corpus of forward models. Combined with only a recorded EEG signal, we are able to estimate both the brain sources and a person-specific forward model by optimizing this parametrization. We thus not only solve an inverse problem, but also optimize over its specification. Our work demonstrates that personalized EEG brain imaging is possible, even when the head geometry and conductivities are unknown.

  19. Diffusion Tensor Imaging Of the Brain in Type 1 Diabetes

    Directory of Open Access Journals (Sweden)

    Jo Ann V. Antenor-Dorsey

    2014-10-01

    Full Text Available Individuals with Type 1 diabetes mellitus (T1DM are required to carefully manage their insulin dosing, dietary intake, and activity levels in order to maintain optimal blood sugar levels. Over time, exposure to hyperglycaemia is known to cause significant damage to the peripheral nervous system, but its impact on the central nervous system has been less well studied. Researchers have begun to explore the cumulative impact of commonly experienced blood glucose fluctuations on brain structure and function in patient populations. To date, these studies have typically used magnetic resonance imaging to measure regional grey and white matter volumes across the brain. However, newer methods, such as diffusion tensor imaging (DTI can measure the microstructural properties of white matter, which can be more sensitive to neurological effects than standard volumetric measures. Studies are beginning to use DTI to understand the impact of T1DM on white matter structure in the human brain. This work, its implications, future directions, and important caveats, are the focus of this review.

  20. Brain Imaging of Nicotinic Receptors in Alzheimer's Disease

    Directory of Open Access Journals (Sweden)

    Jin Wu

    2010-01-01

    Full Text Available Neuronal nicotinic acetylcholine receptors (nAChRs are a family of ligand-gated ion channels which are widely distributed in the human brain. Several lines of evidence suggest that two major subtypes (α4β2 and α7 of nAChRs play an important role in the pathophysiology of Alzheimer's disease (AD. Postmortem studies demonstrated alterations in the density of these subtypes of nAChRs in the brain of patients with AD. Currently, nAChRs are one of the most attractive therapeutic targets for AD. Therefore, several researchers have made an effort to develop novel radioligands that can be used to study quantitatively the distribution of these two subtypes in the human brain with positron emission tomography (PET and single-photon emission computed tomography (SPECT. In this paper, we discuss the current topics on in vivo imaging of two subtypes of nAChRs in the brain of patients with AD.

  1. Meta-analysis of functional brain imaging in specific phobia.

    Science.gov (United States)

    Ipser, Jonathan C; Singh, Leesha; Stein, Dan J

    2013-07-01

    Although specific phobia is a prevalent anxiety disorder, evidence regarding its underlying functional neuroanatomy is inconsistent. A meta-analysis was undertaken to identify brain regions that were consistently responsive to phobic stimuli, and to characterize changes in brain activation following cognitive behavioral therapy (CBT). We searched the PubMed, SCOPUS and PsycINFO databases to identify positron emission tomography and functional magnetic resonance imaging studies comparing brain activation in specific phobia patients and healthy controls. Two raters independently extracted study data from all the eligible studies, and pooled coordinates from these studies using activation likelihood estimation, a quantitative meta-analytic technique. Resulting statistical parametric maps were compared between patients and healthy controls, in response to phobic versus fear-evoking stimuli, and before and after therapy. Thirteen studies were included, comprising 327 participants. Regions that were consistently activated in response to phobic stimuli included the left insula, amygdala, and globus pallidus. Compared to healthy controls, phobic subjects had increased activation in response to phobic stimuli in the left amygdala/globus pallidus, left insula, right thalamus (pulvinar), and cerebellum. Following exposure-based therapy widespread deactivation was observed in the right frontal cortex, limbic cortex, basal ganglia and cerebellum, with increased activation detected in the thalamus. Exposure to phobia-specific stimuli elicits brain activation that is consistent with current understandings of the neuroanatomy of fear conditioning and extinction. There is evidence that the effects of CBT in specific phobia may be mediated through the same underlying neurocircuitry.

  2. Semi-automatic Epileptic Hot Spot Detection in ECD brain SPECT images

    Science.gov (United States)

    Papp, Laszlo; Zuhayra, Maaz; Henze, Eberhard

    A method is proposed to process ECD brain SPECT images representing epileptic hot spots inside the brain. For validation 35 ictal —interictal patient image data were processed. The images were registered by a normalized mutual information method, then the separation of the suspicious and normal brain areas were performed by two threshold-based segmentations. Normalization between the images was performed by local normal brain mean values. Based on the validation made by two medical physicians, minimal human intervention in the segmentation parameters was necessary to detect all epileptic spots and minimize the number of false spots inside the brain.

  3. Automated Brain Tumor Segmentation on MR Images Based on Neutrosophic Set Approach

    OpenAIRE

    Mohan J; Krishnaveni V; Yanhui Huo

    2015-01-01

    Brain tumor segmentation for MR images is a difficult and challenging task due to variation in type, size, location and shape of tumors. This paper presents an efficient and fully automatic brain tumor segmentation technique. This proposed technique includes non local preprocessing, fuzzy intensification to enhance the quality of the MR images, k - means clustering method for brain tumor segmentation.

  4. Some Problems for Representations of Brain Organization Based on Activation in Functional Imaging

    Science.gov (United States)

    Sidtis, John J.

    2007-01-01

    Functional brain imaging has overshadowed traditional lesion studies in becoming the dominant approach to the study of brain-behavior relationships. The proponents of functional imaging studies frequently argue that this approach provides an advantage over lesion studies by observing normal brain activity in vivo without the disruptive effects of…

  5. Intraoperative image updating for brain shift following dural opening.

    Science.gov (United States)

    Fan, Xiaoyao; Roberts, David W; Schaewe, Timothy J; Ji, Songbai; Holton, Leslie H; Simon, David A; Paulsen, Keith D

    2016-09-09

    OBJECTIVE Preoperative magnetic resonance images (pMR) are typically coregistered to provide intraoperative navigation, the accuracy of which can be significantly compromised by brain deformation. In this study, the authors generated updated MR images (uMR) in the operating room (OR) to compensate for brain shift due to dural opening, and evaluated the accuracy and computational efficiency of the process. METHODS In 20 open cranial neurosurgical cases, a pair of intraoperative stereovision (iSV) images was acquired after dural opening to reconstruct a 3D profile of the exposed cortical surface. The iSV surface was registered with pMR to detect cortical displacements that were assimilated by a biomechanical model to estimate whole-brain nonrigid deformation and produce uMR in the OR. The uMR views were displayed on a commercial navigation system and compared side by side with the corresponding coregistered pMR. A tracked stylus was used to acquire coordinate locations of features on the cortical surface that served as independent positions for calculating target registration errors (TREs) for the coregistered uMR and pMR image volumes. RESULTS The uMR views were visually more accurate and well aligned with the iSV surface in terms of both geometry and texture compared with pMR where misalignment was evident. The average misfit between model estimates and measured displacements was 1.80 ± 0.35 mm, compared with the average initial misfit of 7.10 ± 2.78 mm between iSV and pMR, and the average TRE was 1.60 ± 0.43 mm across the 20 patients in the uMR image volume, compared with 7.31 ± 2.82 mm on average in the pMR cases. The iSV also proved to be accurate with an average error of 1.20 ± 0.37 mm. The overall computational time required to generate the uMR views was 7-8 minutes. CONCLUSIONS This study compensated for brain deformation caused by intraoperative dural opening using computational model-based assimilation of iSV cortical surface displacements. The u

  6. Magnetic resonance imaging safety of deep brain stimulator devices.

    Science.gov (United States)

    Oluigbo, Chima O; Rezai, Ali R

    2013-01-01

    Magnetic resonance imaging (MRI) has become the standard of care for the evaluation of different neurological disorders of the brain and spinal cord due to its multiplanar capabilities and excellent soft tissue resolution. With the large and increasing population of patients with implanted deep brain stimulation (DBS) devices, a significant proportion of these patients with chronic neurological diseases require evaluation of their primary neurological disease processes by MRI. The presence of an implanted DBS device in a magnetic resonance environment presents potential hazards. These include the potential for induction of electrical currents or heating in DBS devices, which can result in neurological tissue injury, magnetic field-induced device migration, or disruption of the operational aspects of the devices. In this chapter, we review the basic physics of potential interactions of the MRI environment with implanted DBS devices, summarize results from phantom studies and clinical series, and discuss present recommendations for safe MRI in patients with implanted DBS devices.

  7. Visualizing the blind brain: brain imaging of visual field defects from early recovery to rehabilitation techniques

    Directory of Open Access Journals (Sweden)

    Marika eUrbanski

    2014-09-01

    Full Text Available Visual field defects (VFDs are one of the most common consequences observed after brain injury, especially after a stroke in the posterior cerebral artery territory. Less frequently, tumours, traumatic brain injury, brain surgery or demyelination can also determine various visual disabilities, from a decrease in visual acuity to cerebral blindness. VFD is a factor of bad functional prognosis as it compromises many daily life activities (e.g., obstacle avoidance, driving, and reading and therefore the patient’s quality of life. Spontaneous recovery seems to be limited and restricted to the first six months, with the best chance of improvement at one month. The possible mechanisms at work could be partly due to cortical reorganization in the visual areas (plasticity and/or partly to the use of intact alternative visual routes, first identified in animal studies and possibly underlying the phenomenon of blindsight. Despite processes of early recovery, which is rarely complete, and learning of compensatory strategies, the patient’s autonomy may still be compromised at more chronic stages. Therefore, various rehabilitation therapies based on neuroanatomical knowledge have been developed to improve VFDs. These use eye-movement training techniques (e.g., visual search, saccadic eye movements, reading training, visual field restitution (the Vision Restoration Therapy, VRT, or perceptual learning. In this review, we will focus on studies of human adults with acquired VFDs, which have used different imaging techniques (Positron Emission Tomography: PET, Diffusion Tensor Imaging: DTI, functional Magnetic Resonance Imaging: fMRI, MagnetoEncephalography: MEG or neurostimulation techniques (Transcranial Magnetic Stimulation: TMS; transcranial Direct Current Stimulation, tDCS to show brain activations in the course of spontaneous recovery or after specific rehabilitation techniques.

  8. Functional connectivity of the rodent brain using optical imaging

    Science.gov (United States)

    Guevara Codina, Edgar

    The aim of this thesis is to apply functional connectivity in a variety of animal models, using several optical imaging modalities. Even at rest, the brain shows high metabolic activity: the correlation in slow spontaneous fluctuations identifies remotely connected areas of the brain; hence the term "functional connectivity". Ongoing changes in spontaneous activity may provide insight into the neural processing that takes most of the brain metabolic activity, and so may provide a vast source of disease related changes. Brain hemodynamics may be modified during disease and affect resting-state activity. The thesis aims to better understand these changes in functional connectivity due to disease, using functional optical imaging. The optical imaging techniques explored in the first two contributions of this thesis are Optical Imaging of Intrinsic Signals and Laser Speckle Contrast Imaging, together they can estimate the metabolic rate of oxygen consumption, that closely parallels neural activity. They both have adequate spatial and temporal resolution and are well adapted to image the convexity of the mouse cortex. In the last article, a depth-sensitive modality called photoacoustic tomography was used in the newborn rat. Optical coherence tomography and laminar optical tomography were also part of the array of imaging techniques developed and applied in other collaborations. The first article of this work shows the changes in functional connectivity in an acute murine model of epileptiform activity. Homologous correlations are both increased and decreased with a small dependence on seizure duration. These changes suggest a potential decoupling between the hemodynamic parameters in resting-state networks, underlining the importance to investigate epileptic networks with several independent hemodynamic measures. The second study examines a novel murine model of arterial stiffness: the unilateral calcification of the right carotid. Seed-based connectivity analysis

  9. Three modality image registration of brain SPECT/CT and MR images for quantitative analysis of dopamine transporter imaging

    Science.gov (United States)

    Yamaguchi, Yuzuho; Takeda, Yuta; Hara, Takeshi; Zhou, Xiangrong; Matsusako, Masaki; Tanaka, Yuki; Hosoya, Kazuhiko; Nihei, Tsutomu; Katafuchi, Tetsuro; Fujita, Hiroshi

    2016-03-01

    Important features in Parkinson's disease (PD) are degenerations and losses of dopamine neurons in corpus striatum. 123I-FP-CIT can visualize activities of the dopamine neurons. The activity radio of background to corpus striatum is used for diagnosis of PD and Dementia with Lewy Bodies (DLB). The specific activity can be observed in the corpus striatum on SPECT images, but the location and the shape of the corpus striatum on SPECT images only are often lost because of the low uptake. In contrast, MR images can visualize the locations of the corpus striatum. The purpose of this study was to realize a quantitative image analysis for the SPECT images by using image registration technique with brain MR images that can determine the region of corpus striatum. In this study, the image fusion technique was used to fuse SPECT and MR images by intervening CT image taken by SPECT/CT. The mutual information (MI) for image registration between CT and MR images was used for the registration. Six SPECT/CT and four MR scans of phantom materials are taken by changing the direction. As the results of the image registrations, 16 of 24 combinations were registered within 1.3mm. By applying the approach to 32 clinical SPECT/CT and MR cases, all of the cases were registered within 0.86mm. In conclusions, our registration method has a potential in superimposing MR images on SPECT images.

  10. Characterisation of contrast agent microbubbles for ultrasound imaging and therapy research

    OpenAIRE

    2016-01-01

    The high efficiency with which gas microbubbles can scatter ultrasound compared to the surrounding blood pool or tissues has led to their widespread employment as contrast agents in ultrasound imaging. In recent years their applications have been extended to include super-resolution imaging and the stimulation of localized bio-effects for therapy. The growing exploitation of contrast agents in ultrasound, and in particular these recent developments, have amplified the need to characterize and...

  11. Atlas image labeling of subcortical structures and vascular territories in brain CT images.

    Science.gov (United States)

    Du, Kaifang; Zhang, Li; Nguyen, Tony; Ordy, Vincent; Fichte, Heinz; Ditt, Hendrik; Chefd'hotel, Christophe

    2013-01-01

    We propose a multi-atlas labeling method for subcortical structures and cerebral vascular territories in brain CT images. Each atlas image is registered to the query image by a non-rigid registration and the deformation is then applied to the labeling of the atlas image to obtain the labeling of the query image. Four label fusion strategies (single atlas, most similar atlas, major voting, and STAPLE) were compared. Image similarity values in non-rigid registration were calculated and used to select and rank atlases. Major voting fusion strategy gave the best accuracy, with DSC (Dice similarity coefficient) around 0.85 ± 0.03 for caudate, putamen, and thalamus. The experimental results also show that fusing more atlases does not necessarily yield higher accuracy and we should be able to improve accuracy and decrease computation cost at the same time by selecting a preferred set with the minimum number of atlases.

  12. Anatomical Brain Magnetic Resonance Imaging of Typically Developing Children and Adolescents

    Science.gov (United States)

    Giedd, Jay N.; Lalonde, Francois M.; Celano, Mark J.; White, Samantha L.; Wallace, Gregory L.; Lee, Nancy R.; Lenroot, Rhoshel K.

    2009-01-01

    Methodological issues relevant to magnetic resonance imaging studies of brain anatomy are discussed along with the findings on the neuroanatomic changes during childhood and adolescence. The development of the brain is also discussed.

  13. Magnetic resonance imaging of post-ischemic blood-brain barrier damage with PEGylated iron oxide nanoparticles

    Science.gov (United States)

    Liu, Dong-Fang; Qian, Cheng; An, Yan-Li; Chang, Di; Ju, Sheng-Hong; Teng, Gao-Jun

    2014-11-01

    Blood-brain barrier (BBB) damage during ischemia may induce devastating consequences like cerebral edema and hemorrhagic transformation. This study presents a novel strategy for dynamically imaging of BBB damage with PEGylated supermagnetic iron oxide nanoparticles (SPIONs) as contrast agents. The employment of SPIONs as contrast agents made it possible to dynamically image the BBB permeability alterations and ischemic lesions simultaneously with T2-weighted MRI, and the monitoring could last up to 24 h with a single administration of PEGylated SPIONs in vivo. The ability of the PEGylated SPIONs to highlight BBB damage by MRI was demonstrated by the colocalization of PEGylated SPIONs with Gd-DTPA after intravenous injection of SPION-PEG/Gd-DTPA into a mouse. The immunohistochemical staining also confirmed the leakage of SPION-PEG from cerebral vessels into parenchyma. This study provides a novel and convenient route for imaging BBB alteration in the experimental ischemic stroke model.

  14. Functional magnetic resonance imaging of the brain: A quick review

    Directory of Open Access Journals (Sweden)

    Vaghela Viratsinh

    2010-01-01

    Full Text Available Ability to non-invasively map the hemodynamic changes occurring focally in areas of brain involved in various motor, sensory and cognitive functions by functional magnetic resonance imaging (fMRI has revolutionized research in neuroscience in the last two decades. This technique has already gained clinical use especially in pre-surgical evaluation of epilepsy and neurosurgical planning of resection of mass lesions adjacent to eloquent cortex. In this review we attempt to illustrate basic principles and techniques of fMRI, its applications, practical points to consider while performing and evaluating clinical fMRI and its limitations.

  15. Brain tumor imaging of rat fresh tissue using terahertz spectroscopy

    Science.gov (United States)

    Yamaguchi, Sayuri; Fukushi, Yasuko; Kubota, Oichi; Itsuji, Takeaki; Ouchi, Toshihiko; Yamamoto, Seiji

    2016-07-01

    Tumor imaging by terahertz spectroscopy of fresh tissue without dye is demonstrated using samples from a rat glioma model. The complex refractive index spectrum obtained by a reflection terahertz time-domain spectroscopy system can discriminate between normal and tumor tissues. Both the refractive index and absorption coefficient of tumor tissues are higher than those of normal tissues and can be attributed to the higher cell density and water content of the tumor region. The results of this study indicate that terahertz technology is useful for detecting brain tumor tissue.

  16. Content-based image retrieval in the World Wide Web: a web agent for fetching portraits

    Science.gov (United States)

    Muenkelt, Olaf; Kaufmann, Oliver; Eckstein, Wolfgang

    1997-01-01

    This article propose a way to automatically retrieve images from the world-wide-web using a semantic description for images and an agent concept for the retrieval of images. The system represents image in a textual way, e.g. look for a portrait of the a specific person, or fetch an image showing a countryside in Southern California. This textual descriptions are fed in search machines, e.g. yahoo, alta- vista. The resulting html documents are seeked for links. The next step subsequently processes each link by fetching the document other the net, converting it to an ascii representation, and performing a full text search by using the image description. This leads to starting points of images which are retrieved via a web-agent. The image descriptions are decomposed in a set of parts containing image operations which are further processed, e.g. a set for representing the background of a portrait tries to find a homogeneous region in the image because this is likely to find in a portrait. Additional operations are performed on the foreground, i.e. the image region which contains e.g. the face of a person. The system is realized using two C++ libraries: one for building up web-agents, LIWA++, and one for processing images, HORUS.

  17. Nanoparticle-Based Systems for T1-Weighted Magnetic Resonance Imaging Contrast Agents

    Science.gov (United States)

    Zhu, Derong; Liu, Fuyao; Ma, Lina; Liu, Dianjun; Wang, Zhenxin

    2013-01-01

    Because magnetic resonance imaging (MRI) contrast agents play a vital role in diagnosing diseases, demand for new MRI contrast agents, with an enhanced sensitivity and advanced functionalities, is very high. During the past decade, various inorganic nanoparticles have been used as MRI contrast agents due to their unique properties, such as large surface area, easy surface functionalization, excellent contrasting effect, and other size-dependent properties. This review provides an overview of recent progress in the development of nanoparticle-based T1-weighted MRI contrast agents. The chemical synthesis of the nanoparticle-based contrast agents and their potential applications were discussed and summarized. In addition, the recent development in nanoparticle-based multimodal contrast agents including T1-weighted MRI/computed X-ray tomography (CT) and T1-weighted MRI/optical were also described, since nanoparticles may curtail the shortcomings of single mode contrast agents in diagnostic and clinical settings by synergistically incorporating functionality. PMID:23698781

  18. Perfusion imaging with computed tomography: brain and beyond

    Energy Technology Data Exchange (ETDEWEB)

    Miles, K.A. [Div. of Clinical and Lab. Investigation, Brighton and Sussex Medical School, Univ. of Sussex, Falmer, Brighton (United Kingdom)

    2006-01-10

    The availability of rapid imaging with multidetector CT systems and commercial analysis software has made perfusion imaging with CT an everyday technique, not only for the brain but also for other body organs. Perfusion imaging is usually performed as an adjunct to a conventional CT examination and is therefore particularly appropriate when a conventional CT is part of routine clinical protocols. The derived values are reproducible and have been validated against a range of reference techniques. Within neuroradiology, perfusion CT has attracted interest in the assessment of acute stroke but can also be used to assess secondary injury in head trauma and as an adjunct to CT angiography to evaluate cerebral spasm in subarachnoid haemorrhage. Within oncology, perfusion CT provides an imaging correlate for tumour vascularity that can be used to discriminate benign and malignant lesions, as an indicator of tumour aggressiveness, to reveal occult tumour and improve the delineation of tumours during radiotherapy planning, and as a functional assessment of tumour response to therapy. By exploiting the ability of CT systems to quantify contrast enhancement. CT perfusion imaging uses contrast media to assess vascular physiology and so improve diagnosis, prognosis, treatment selection and therapy monitoring. (orig.)

  19. A Novel Polyacrylamide Magnetic Nanoparticle Contrast Agent for Molecular Imaging using MRI

    Directory of Open Access Journals (Sweden)

    Bradford A. Moffat

    2003-10-01

    Full Text Available A novel Polyacrylamide superparamagnetic iron oxide nanoparticle platform is described which has been synthetically prepared such that multiple crystals of iron oxide are encapsulated within a single Polyacrylamide matrix (PolyAcrylamide Magnetic [PAM] nanoparticles. This formulation provides for an extremely large T2 and T2* relaxivity of between 620 and 1140 sec−1 mM−1. Administration of PAM nanoparticles into rats bearing orthotopic 9L gliomas allowed quantitative pharmacokinetic analysis of the uptake of nanoparticles in the vasculature, brain, and glioma. Addition of polyethylene glycol of varying sizes (0.6, 2, and 10 kDa to the surface of the PAM nanoparticles resulted in an increase in plasma half-life and affected tumor uptake and retention of the nanoparticles as quantified by changes in tissue contrast using MRI. The flexible formulation of these nanoparticles suggests that future modifications could be accomplished allowing for their use as a targeted molecular imaging contrast agent and/or therapeutic platform for multiple indications.

  20. Brain tumours at 7T MRI compared to 3T - contrast effect after half and full standard contrast agent dose: initial results

    Energy Technology Data Exchange (ETDEWEB)

    Noebauer-Huhmann, Iris-Melanie; Weber, M. [Medical University of Vienna, High Field MR Centre, Department of Biomedical Imaging and Image-guided Therapy, Vienna (Austria); Medical University of Vienna, Division of Neuroradiology and Musculoskeletal Radiology, Department of Biomedical Imaging and Image-guided Therapy, Vienna (Austria); Szomolanyi, P.; Juras, V. [Medical University of Vienna, High Field MR Centre, Department of Biomedical Imaging and Image-guided Therapy, Vienna (Austria); Slovak Academy of Sciences, Department of Imaging Methods, Institute of Measurement Science, Bratislava (Slovakia); Kronnerwetter, C. [Medical University of Vienna, High Field MR Centre, Department of Biomedical Imaging and Image-guided Therapy, Vienna (Austria); Widhalm, G. [Medical University of Vienna, Department of Neurosurgery, Vienna (Austria); Nemec, S.; Prayer, D. [Medical University of Vienna, Division of Neuroradiology and Musculoskeletal Radiology, Department of Biomedical Imaging and Image-guided Therapy, Vienna (Austria); Ladd, M.E. [University Duisburg-Essen, Erwin L. Hahn Institute for Magnetic Resonance Imaging, Essen (Germany); German Cancer Research Center (DKFZ), Division of Medical Physics in Radiology, Heidelberg (Germany); Trattnig, S. [Medical University of Vienna, High Field MR Centre, Department of Biomedical Imaging and Image-guided Therapy, Vienna (Austria); Ludwig Boltzmann Institute for Experimental and Clinical Traumatology, Austrian Cluster for Tissue Regeneration, Vienna (Austria)

    2015-01-15

    To compare the contrast agent effect of a full dose and half the dose of gadobenate dimeglumine in brain tumours at 7 Tesla (7T) MR versus 3 Tesla (3T). Ten patients with primary brain tumours or metastases were examined. Signal intensities were assessed in the lesion and normal brain. Tumour-to-brain contrast and lesion enhancement were calculated. Additionally, two independent readers subjectively graded the image quality and artefacts. The enhanced mean tumour-to-brain contrast and lesion enhancement were significantly higher at 7T than at 3T for both half the dose (91.8 ± 45.8 vs. 43.9 ± 25.3 [p = 0.010], 128.1 ± 53.7 vs. 75.5 ± 32.4 [p = 0.004]) and the full dose (129.2 ± 50.9 vs. 66.6 ± 33.1 [p = 0.002], 165.4 ± 54.2 vs. 102.6 ± 45.4 [p = 0.004]). Differences between dosages at each field strength were also significant. Lesion enhancement was higher with half the dose at 7T than with the full dose at 3T (p =.037), while the tumour-to-brain contrast was not significantly different. Subjectively, contrast enhancement, visibility, and lesion delineation were better at 7T and with the full dose. All parameters were rated as good, at the least. Half the routine contrast agent dose at 7T provided higher lesion enhancement than the full dose at 3T which indicates the possibility of dose reduction at 7T. (orig.)

  1. Intra-individual, randomised comparison of the MRI contrast agents gadobutrol versus gadoteridol in patients with primary and secondary brain tumours, evaluated in a blinded read

    Energy Technology Data Exchange (ETDEWEB)

    Koenig, M. [Klinikum Luenen St. Marien-Hospital, Department of Diagnostic and Interventional Radiology and Neuroradiology, Luenen (Germany); Schulte-Altedorneburg, G. [Staedtisches Klinikum Muenchen Harlaching, Department of Diagnostic and Interventional Radiology, Neuroradiology and Nuclear Medicine, Muenchen (Germany); Piontek, M.; Heuser, L. [Universitaetsklinikum Knappschaftskrankenhaus GmbH, Department of Diagnostic and Interventional Radiology, Neuroradiology and Nuclear Medicine, Bochum (Germany); Hentsch, A. [Radiologisches Institut Hohenzollernstrasse, Koblenz (Germany); Spangenberg, P. [Universitaetsklinikum Knappschaftskrankenhaus GmbH, Department of Neurosurgery, Bochum (Germany); Schwenke, C. [SCO:SSiS, Berlin (Germany); Harders, A. [Universitaetsklinikum Knappschaftskrankenhaus GmbH, Department of Neurosurgery Knappschaftskrankenhaus, Bochum (Germany)

    2013-12-15

    To prove that 1.0 M gadobutrol provides superior contrast enhancement and MRI image characteristics of primary and secondary brain tumours compared with 0.5 M gadoteridol, thereby providing superior diagnostic information. Brain MRI was performed in two separate examinations in patients scheduled for neurosurgery. Independent injections of 1.0 M gadobutrol and 0.5 M gadoteridol at doses of 0.1 mmol Gd/kg body weight were administered per patient in randomised order. Evaluation was performed in an off-site blinded read. Fifty-one patients in the full analysis set (FAS) were eligible for efficacy analysis and 44 for the per-protocol analysis. For the primary efficacy variable ''preference in contrast enhancement for one contrast agent or the other'', the rate of ''gadobutrol preferred'' was estimated at 0.73 (95 % confidence interval 0.61; 0.83), showing significant superiority of gadobutrol over gadoteridol. Calculated lesion-to-brain contrast and the results of all qualitative secondary efficacy variables were also in favour of gadobutrol. Keeping a sufficient time delay after contrast application proved to be essential to get optimal image quality. Compared with 0.5 M gadoteridol, 1.0 M gadobutrol was proven to have significantly superior contrast enhancement characteristics in a routine MRI protocol of primary and secondary brain tumours. (orig.)

  2. Emerging Techniques in Brain Tumor Imaging: What Radiologists Need to Know

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Minjae; Kim, Ho Sung [Department of Radiology and Research Institute of Radiology, University of Ulsan College of Medicine, Asan Medical Center, Seoul 05505 (Korea, Republic of)

    2016-11-01

    Among the currently available brain tumor imaging, advanced MR imaging techniques, such as diffusion-weighted MR imaging and perfusion MR imaging, have been used for solving diagnostic challenges associated with conventional imaging and for monitoring the brain tumor treatment response. Further development of advanced MR imaging techniques and postprocessing methods may contribute to predicting the treatment response to a specific therapeutic regimen, particularly using multi-modality and multiparametric imaging. Over the next few years, new imaging techniques, such as amide proton transfer imaging, will be studied regarding their potential use in quantitative brain tumor imaging. In this review, the pathophysiologic considerations and clinical validations of these promising techniques are discussed in the context of brain tumor characterization and treatment response.

  3. Emerging techniques in brain tumor imaging: What radiologists need to know

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Min Jae; Kim, Ho Sung [University of Ulsan College of Medicine, Asan Medical Center, Seoul (Korea, Republic of)

    2016-09-15

    Among the currently available brain tumor imaging, advanced MR imaging techniques, such as diffusion-weighted MR imaging and perfusion MR imaging, have been used for solving diagnostic challenges associated with conventional imaging and for monitoring the brain tumor treatment response. Further development of advanced MR imaging techniques and postprocessing methods may contribute to predicting the treatment response to a specific therapeutic regimen, particularly using multi-modality and multiparametric imaging. Over the next few years, new imaging techniques, such as amide proton transfer imaging, will be studied regarding their potential use in quantitative brain tumor imaging. In this review, the pathophysiologic considerations and clinical validations of these promising techniques are discussed in the context of brain tumor characterization and treatment response.

  4. Serotonin transporter and dopamine transporter imaging in the canine brain

    Energy Technology Data Exchange (ETDEWEB)

    Peremans, Kathelijne [Department of Medical Imaging, Faculty of Veterinary Sciences, Ghent University, B-9000 Ghent (Belgium); Goethals, Ingeborg [Division of Nuclear Medicine, University Hospital Ghent, B-9000 Ghent (Belgium); De Vos, Filip [Laboratory of Radiopharmacy, Pharmaceutical Sciences, Ghent University, B-9000 Ghent (Belgium); Dobbeleir, A. [Department of Medical Imaging, Faculty of Veterinary Sciences, Ghent University, B-9000 Ghent (Belgium); Ham, Hamphrey [Division of Nuclear Medicine, University Hospital Ghent, B-9000 Ghent (Belgium); Van Bree, Henri [Department of Medical Imaging, Faculty of Veterinary Sciences, Ghent University, B-9000 Ghent (Belgium); Heeringen, Cees van [Department of Psychiatry and Medical Psychology, Faculty of Medical and Health Sciences, Ghent University, B-9000, Ghent (Belgium); Audenaert, Kurt [Division of Nuclear Medicine, University Hospital Ghent, B-9000 Ghent (Belgium) and Department of Psychiatry and Medical Psychology, Faculty of Medical and Health Sciences, Ghent University, B-9000, Ghent (Belgium)]. E-mail: kurt.audenaert@ugent.be

    2006-10-15

    The serotonergic and dopaminergic systems are involved in a wide range of emotional and behavioral aspects of animals and humans and are involved in many neuropsychiatric disorders. Selective serotonin (5-HT) reuptake inhibitors (SSRIs) are designed to block the 5-HT transporter (SERT), thereby increasing the available 5-HT in the brain. Functional imaging with specific SERT and dopamine transporter (DAT) ligands contributes to the study of the SSRI-transporter interaction. First, we evaluated the feasibility of a canine model in the study of the SERT and DAT with the radioligands [{sup 123}I]-{beta}-CIT and [{sup 123}I]-FP-CIT as well as single-photon emission computed tomography imaging. Second, we studied the effect of SSRIs (sertraline, citalopram and escitalopram) on the SERT and DAT in two dogs. The position of the canine model in the study of the SERT and DAT is discussed and compared with other animal models.

  5. Magnetic Resonance Imaging Profile of Blood–Brain Barrier Injury in Patients With Acute Intracerebral Hemorrhage

    Science.gov (United States)

    Aksoy, Didem; Bammer, Roland; Mlynash, Michael; Venkatasubramanian, Chitra; Eyngorn, Irina; Snider, Ryan W.; Gupta, Sandeep N.; Narayana, Rashmi; Fischbein, Nancy; Wijman, Christine A. C.

    2013-01-01

    Background Spontaneous intracerebral hemorrhage (ICH) is associated with blood–brain barrier (BBB) injury, which is a poorly understood factor in ICH pathogenesis, potentially contributing to edema formation and perihematomal tissue injury. We aimed to assess and quantify BBB permeability following human spontaneous ICH using dynamic contrast‐enhanced magnetic resonance imaging (DCE MRI). We also investigated whether hematoma size or location affected the amount of BBB leakage. Methods and Results Twenty‐five prospectively enrolled patients from the Diagnostic Accuracy of MRI in Spontaneous intracerebral Hemorrhage (DASH) study were examined using DCE MRI at 1 week after symptom onset. Contrast agent dynamics in the brain tissue and general tracer kinetic modeling were used to estimate the forward leakage rate (Ktrans) in regions of interest (ROI) in and surrounding the hematoma and in contralateral mirror–image locations (control ROI). In all patients BBB permeability was significantly increased in the brain tissue immediately adjacent to the hematoma, that is, the hematoma rim, compared to the contralateral mirror ROI (P30 mL) had higher Ktrans values than small hematomas (P<0.005). Ktrans values of lobar hemorrhages were significantly higher than the Ktrans values of deep hemorrhages (P<0.005), independent of hematoma volume. Higher Ktrans values were associated with larger edema volumes. Conclusions BBB leakage in the brain tissue immediately bordering the hematoma can be measured and quantified by DCE MRI in human ICH. BBB leakage at 1 week is greater in larger hematomas as well as in hematomas in lobar locations and is associated with larger edema volumes. PMID:23709564

  6. Optimising rigid motion compensation for small animal brain PET imaging

    Science.gov (United States)

    Spangler-Bickell, Matthew G.; Zhou, Lin; Kyme, Andre Z.; De Laat, Bart; Fulton, Roger R.; Nuyts, Johan

    2016-10-01

    Motion compensation (MC) in PET brain imaging of awake small animals is attracting increased attention in preclinical studies since it avoids the confounding effects of anaesthesia and enables behavioural tests during the scan. A popular MC technique is to use multiple external cameras to track the motion of the animal’s head, which is assumed to be represented by the motion of a marker attached to its forehead. In this study we have explored several methods to improve the experimental setup and the reconstruction procedures of this method: optimising the camera-marker separation; improving the temporal synchronisation between the motion tracker measurements and the list-mode stream; post-acquisition smoothing and interpolation of the motion data; and list-mode reconstruction with appropriately selected subsets. These techniques have been tested and verified on measurements of a moving resolution phantom and brain scans of an awake rat. The proposed techniques improved the reconstructed spatial resolution of the phantom by 27% and of the rat brain by 14%. We suggest a set of optimal parameter values to use for awake animal PET studies and discuss the relative significance of each parameter choice.

  7. Tomographic brain imaging with nucleolar detail and automatic cell counting

    Science.gov (United States)

    Hieber, Simone E.; Bikis, Christos; Khimchenko, Anna; Schweighauser, Gabriel; Hench, Jürgen; Chicherova, Natalia; Schulz, Georg; Müller, Bert

    2016-09-01

    Brain tissue evaluation is essential for gaining in-depth insight into its diseases and disorders. Imaging the human brain in three dimensions has always been a challenge on the cell level. In vivo methods lack spatial resolution, and optical microscopy has a limited penetration depth. Herein, we show that hard X-ray phase tomography can visualise a volume of up to 43 mm3 of human post mortem or biopsy brain samples, by demonstrating the method on the cerebellum. We automatically identified 5,000 Purkinje cells with an error of less than 5% at their layer and determined the local surface density to 165 cells per mm2 on average. Moreover, we highlight that three-dimensional data allows for the segmentation of sub-cellular structures, including dendritic tree and Purkinje cell nucleoli, without dedicated staining. The method suggests that automatic cell feature quantification of human tissues is feasible in phase tomograms obtained with isotropic resolution in a label-free manner.

  8. Insect brains use image interpolation mechanisms to recognise rotated objects.

    Directory of Open Access Journals (Sweden)

    Adrian G Dyer

    Full Text Available Recognising complex three-dimensional objects presents significant challenges to visual systems when these objects are rotated in depth. The image processing requirements for reliable individual recognition under these circumstances are computationally intensive since local features and their spatial relationships may significantly change as an object is rotated in the horizontal plane. Visual experience is known to be important in primate brains learning to recognise rotated objects, but currently it is unknown how animals with comparatively simple brains deal with the problem of reliably recognising objects when seen from different viewpoints. We show that the miniature brain of honeybees initially demonstrate a low tolerance for novel views of complex shapes (e.g. human faces, but can learn to recognise novel views of stimuli by interpolating between or 'averaging' views they have experienced. The finding that visual experience is also important for bees has important implications for understanding how three dimensional biologically relevant objects like flowers are recognised in complex environments, and for how machine vision might be taught to solve related visual problems.

  9. Cognitive neuroscience and brain imaging in bipolar disorder.

    Science.gov (United States)

    Clark, Luke; Sahakian, Barbara J

    2008-01-01

    Bipolar disorder is characterized by a combination of state-related changes in psychological function that are restricted to illness episodes, coupled with trait-related changes that persist through periods of remission, irrespective of symptom status. This article reviews studies that have investigated the brain systems involved in these state- and trait-related changes, using two techniques: (i) indirect measures of neurocognitive function, and (ii) direct neuroimaging measures of brain function during performance of a cognitive task. Studies of neurocognitive function in bipolar disorder indicate deficits in three core domains: attention, executive function, and emotional processing. Functional imaging studies implicate pathophysiology in distributed neural circuitry that includes the prefrontal and anterior cingulate cortices, as well as subcortical limbic structures including the amygdala and the ventral striatum. Whilst there have been clear advances in our understanding of brain changes in bipolar disorder, there are limited data in bipolar depression, and there is limited understanding of the influence of clinical variables including medication status, illness severity, and specific symptom dimensions.

  10. Quantitative Imaging of Cell-Permeable Magnetic Resonance Contrast Agents Using X-Ray Fluorescence

    Directory of Open Access Journals (Sweden)

    Paul J. Endres

    2006-10-01

    Full Text Available The inability to transduce cellular membranes is a limitation of current magnetic resonance imaging probes used in biologic and clinical settings. This constraint confines contrast agents to extracellular and vascular regions of the body, drastically reducing their viability for investigating processes and cycles in developmental biology. Conversely, a contrast agent with the ability to permeate cell membranes could be used in visualizing cell patterning, cell fate mapping, gene therapy, and, eventually, noninvasive cancer diagnosis. Therefore, we describe the synthesis and quantitative imaging of four contrast agents with the capability to cross cell membranes in sufficient quantity for detection. Each agent is based on the conjugation of a Gd(III chelator with a cellular transduction moiety. Specifically, we coupled Gd(III–diethylenetriaminepentaacetic acid DTPA and Gd(III–1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid with an 8–amino acid polyarginine oligomer and an amphipathic stilbene molecule, 4-amino-4'-(N,N-dimethylaminostilbene. The imaging modality that provided the best sensitivity and spatial resolution for direct detection of the contrast agents is synchrotron radiation x-ray fluorescence (SR-XRF. Unlike optical microscopy, SR-XRF provides two-dimensional images with resolution 103 better than 153Gd gamma counting, without altering the agent by organic fluorophore conjugation. The transduction efficiency of the intracellular agents was evaluated by T1 analysis and inductively coupled plasma mass spectrometry to determine the efficacy of each chelate-transporter combination.

  11. Magnetic resonance imaging based noninvasive measurements of brain hemodynamics in neonates

    DEFF Research Database (Denmark)

    De Vis, Jill B; Alderliesten, Thomas; Hendrikse, Jeroen

    2016-01-01

    Perinatal disturbances of brain hemodynamics can have a detrimental effect on the brain's parenchyma with consequently adverse neurodevelopmental outcome. Noninvasive, reliable tools to evaluate the neonate's brain hemodynamics are scarce. Advances in magnetic resonance imaging have provided new...... methods to noninvasively assess brain hemodynamics. More recently these methods have made their transition to the neonatal population. The aim of this review is twofold. Firstly, to describe these newly available noninvasive methods to investigate brain hemodynamics in neonates. Secondly, to discuss...

  12. Magnetic nanobeads as potential contrast agents for magnetic resonance imaging.

    Science.gov (United States)

    Pablico-Lansigan, Michele H; Hickling, William J; Japp, Emily A; Rodriguez, Olga C; Ghosh, Anup; Albanese, Chris; Nishida, Maki; Van Keuren, Edward; Fricke, Stanley; Dollahon, Norman; Stoll, Sarah L

    2013-10-22

    Metal-oxo clusters have been used as building blocks to form hybrid nanomaterials and evaluated as potential MRI contrast agents. We have synthesized a biocompatible copolymer based on a water stable, nontoxic, mixed-metal-oxo cluster, Mn8Fe4O12(L)16(H2O)4, where L is acetate or vinyl benzoic acid, and styrene. The cluster alone was screened by NMR for relaxivity and was found to be a promising T2 contrast agent, with r1 = 2.3 mM(-1) s(-1) and r2 = 29.5 mM(-1) s(-1). Initial cell studies on two human prostate cancer cell lines, DU-145 and LNCap, reveal that the cluster has low cytotoxicity and may be potentially used in vivo. The metal-oxo cluster Mn8Fe4(VBA)16 (VBA = vinyl benzoic acid) can be copolymerized with styrene under miniemulsion conditions. Miniemulsion allows for the formation of nanometer-sized paramagnetic beads (~80 nm diameter), which were also evaluated as a contrast agent for MRI. These highly monodispersed, hybrid nanoparticles have enhanced properties, with the option for surface functionalization, making them a promising tool for biomedicine. Interestingly, both relaxivity measurements and MRI studies show that embedding the Mn8Fe4 core within a polymer matrix decreases r2 effects with little effect on r1, resulting in a positive T1 contrast enhancement.

  13. Diffusion-weighted imaging in normal fetal brain maturation

    Energy Technology Data Exchange (ETDEWEB)

    Schneider, J.F. [University Children' s Hospital UKBB, Department of Pediatric Radiology, Basel (Switzerland); Confort-Gouny, S.; Le Fur, Y.; Viout, P.; Cozzone, P. [UMR-CNRS 6612, Faculte de Medecine, Universite de la Mediterranee, Centre de Resonance Magnetique Biologique et Medicale, Marseille (France); Bennathan, M.; Chapon, F.; Fogliarini, C.; Girard, N. [Universite de la Mediterranee, Department of Neuroradiology AP-HM Timone, Marseille (France)

    2007-09-15

    Diffusion-weighted imaging (DWI) provides information about tissue maturation not seen on conventional magnetic resonance imaging. The aim of this study is to analyze the evolution over time of the apparent diffusion coefficient (ADC) of normal fetal brain in utero. DWI was performed on 78 fetuses, ranging from 23 to 37 gestational weeks (GW). All children showed at follow-up a normal neurological evaluation. ADC values were obtained in the deep white matter (DWM) of the centrum semiovale, the frontal, parietal, occipital and temporal lobe, in the cerebellar hemisphere, the brainstem, the basal ganglia (BG) and the thalamus. Mean ADC values in supratentorial DWM areas (1.68 {+-} 0.05 mm{sup 2}/s) were higher compared with the cerebellar hemisphere (1.25 {+-} 0.06 mm{sup 2}/s) and lowest in the pons (1.11 {+-} 0.05 mm{sup 2}/s). Thalamus and BG showed intermediate values (1.25 {+-} 0.04 mm{sup 2}/s). Brainstem, cerebellar hemisphere and thalamus showed a linear negative correlation with gestational age. Supratentorial areas revealed an increase in ADC values, followed by a decrease after the 30th GW. This study provides a normative data set that allows insights in the normal fetal brain maturation in utero, which has not yet been observed in previous studies on premature babies. (orig.)

  14. DPABI: Data Processing & Analysis for (Resting-State) Brain Imaging.

    Science.gov (United States)

    Yan, Chao-Gan; Wang, Xin-Di; Zuo, Xi-Nian; Zang, Yu-Feng

    2016-07-01

    Brain imaging efforts are being increasingly devoted to decode the functioning of the human brain. Among neuroimaging techniques, resting-state fMRI (R-fMRI) is currently expanding exponentially. Beyond the general neuroimaging analysis packages (e.g., SPM, AFNI and FSL), REST and DPARSF were developed to meet the increasing need of user-friendly toolboxes for R-fMRI data processing. To address recently identified methodological challenges of R-fMRI, we introduce the newly developed toolbox, DPABI, which was evolved from REST and DPARSF. DPABI incorporates recent research advances on head motion control and measurement standardization, thus allowing users to evaluate results using stringent control strategies. DPABI also emphasizes test-retest reliability and quality control of data processing. Furthermore, DPABI provides a user-friendly pipeline analysis toolkit for rat/monkey R-fMRI data analysis to reflect the rapid advances in animal imaging. In addition, DPABI includes preprocessing modules for task-based fMRI, voxel-based morphometry analysis, statistical analysis and results viewing. DPABI is designed to make data analysis require fewer manual operations, be less time-consuming, have a lower skill requirement, a smaller risk of inadvertent mistakes, and be more comparable across studies. We anticipate this open-source toolbox will assist novices and expert users alike and continue to support advancing R-fMRI methodology and its application to clinical translational studies.

  15. An improved brain image classification technique with mining and shape prior segmentation procedure.

    Science.gov (United States)

    Rajendran, P; Madheswaran, M

    2012-04-01

    The shape prior segmentation procedure and pruned association rule with ImageApriori algorithm has been used to develop an improved brain image classification system are presented in this paper. The CT scan brain images have been classified into three categories namely normal, benign and malignant, considering the low-level features extracted from the images and high level knowledge from specialists to enhance the accuracy in decision process. The experimental results on pre-diagnosed brain images showed 97% sensitivity, 91% specificity and 98.5% accuracy. The proposed algorithm is expected to assist the physicians for efficient classification with multiple key features per image.

  16. Optimizing brain tumor resection. Midfield interventional MR imaging.

    Science.gov (United States)

    Alexander, E

    2001-11-01

    The development of the intraoperative MR imager represents an important example of creative vision and interdisciplinary teamwork. The result is a remarkable tool for neurosurgical applications. MRT allows surgical manipulation under direct visualization of the intracranial contents through the eye of the surgeon and through the volumetric images of the MR imaging system. This technology can be applied to cranial and spinal cases, and forseeably can encompass application to the entire gamut of neurosurgical efforts. The author's experience has been that this device is easy and comfortable for the surgeon to use. Image acquisition, giving views in the plane of choice, lasts no more than 2 to 60 seconds (depending on the imaging method), and does not increase the duration of a given procedure substantially. The author believes that the information received through intraoperative MR imaging scanning ultimately will contribute to decreasing the duration of surgery. Future possibilities include combining the intraoperative MR imager with other technologies, such as the endoscope, focused ultrasound, robotics, and the evaluation of brain function intraoperatively. The development of the intraoperative MR imager marks a significant advance in neurosurgery, an advance that will revolutionize intraoperative visualization as fully as the operating microscope. The combination of intraoperative visualization and precise surgical navigation is unparalleled, and its enhancement of surgical applications will be widespread. Considering the remarkable potential of the intraoperative MR imager for neurosurgical applications, optimal magnet design, image quality, and navigational methods are necessary to capitalize on the advantages of this revolutionary tool. The intraoperative MR imaging system that the author's team has developed and used has combined these features, and allows the performance of open surgical procedures without the need of patient or magnet repositioning. By

  17. Cationic albumin-conjugated chelating agent as a novel brain drug delivery system in neurodegeneration.

    Science.gov (United States)

    Kamalinia, Golnaz; Khodagholi, Fariba; Shaerzadeh, Fatemeh; Tavssolian, Faranak; Chaharband, Farkhondeh; Atyabi, Fatemeh; Sharifzadeh, Mohammad; Amini, Mohsen; Dinarvand, Rassoul

    2015-11-01

    The critical role of metal ions and in particular iron in oxidative stress and protein aggregation offers chelation therapy as a sensible pharmaceutical strategy in oxidative stress-induced neuronal damages. In this research, we conjugated an iron-chelating agent, deferasirox, to cationized human serum albumin molecules in order to develop a novel brain delivery system for the management of neurodegenerative disorders due to the significant role of oxidative stress-induced neuronal injury in such diseases. Cationized albumin is known to be able to transport to brain tissue via adsorptive-mediated transcytosis. The developed structures were molecularly characterized, and their conjugation ratio was determined. PC12 cell line was utilized to evaluate the neuroprotective features of these newly developed molecules in the presence of hydrogen peroxide neuronal damage and to identify the mechanisms behind the observed neuronal protection including apoptotic and autophagic pathways. Furthermore, a rat model of Alzheimer's disease was utilized to evaluate the impact of conjugated structures in vivo. Data analysis revealed that the conjugated species were able to hinder apoptotic cell death while enhancing autophagic process. The developed conjugated species were also able to attenuate amyloid beta-induced learning deficits when administered peripherally.

  18. Parkia biglobosa Improves Mitochondrial Functioning and Protects against Neurotoxic Agents in Rat Brain Hippocampal Slices

    Directory of Open Access Journals (Sweden)

    Kayode Komolafe

    2014-01-01

    Full Text Available Objective. Methanolic leaf extracts of Parkia biglobosa, PBE, and one of its major polyphenolic constituents, catechin, were investigated for their protective effects against neurotoxicity induced by different agents on rat brain hippocampal slices and isolated mitochondria. Methods. Hippocampal slices were preincubated with PBE (25, 50, 100, or 200 µg/mL or catechin (1, 5, or 10 µg/mL for 30 min followed by further incubation with 300 µM H2O2, 300 µM SNP, or 200 µM PbCl2 for 1 h. Effects of PBE and catechin on SNP- or CaCl2-induced brain mitochondrial ROS formation and mitochondrial membrane potential (ΔΨm were also determined. Results. PBE and catechin decreased basal ROS generation in slices and blunted the prooxidant effects of neurotoxicants on membrane lipid peroxidation and nonprotein thiol contents. PBE rescued hippocampal cellular viability from SNP damage and caused a significant boost in hippocampus Na+, K+-ATPase activity but with no effect on the acetylcholinesterase activity. Both PBE and catechin also mitigated SNP- or CaCl2-dependent mitochondrial ROS generation. Measurement by safranine fluorescence however showed that the mild depolarization of the ΔΨm by PBE was independent of catechin. Conclusion. The results suggest that the neuroprotective effect of PBE is dependent on its constituent antioxidants and mild mitochondrial depolarization propensity.

  19. PET imaging reveals brain functional changes in internet gaming disorder

    Energy Technology Data Exchange (ETDEWEB)

    Tian, Mei; Zhang, Ying; Du, Fenglei; Hou, Haifeng; Chao, Fangfang; Zhang, Hong [The Second Hospital of Zhejiang University School of Medicine, Department of Nuclear Medicine, Hangzhou, Zhejiang (China); Key Laboratory of Medical Molecular Imaging of Zhejiang Province, Hangzhou (China); Chen, Qiaozhen [The Second Hospital of Zhejiang University School of Medicine, Department of Nuclear Medicine, Hangzhou, Zhejiang (China); The Second Affiliated Hospital of Zhejiang University School of Medicine, Department of Psychiatry, Hangzhou (China)

    2014-07-15

    Internet gaming disorder is an increasing problem worldwide, resulting in critical academic, social, and occupational impairment. However, the neurobiological mechanism of internet gaming disorder remains unknown. The aim of this study is to assess brain dopamine D{sub 2} (D{sub 2})/Serotonin 2A (5-HT{sub 2A}) receptor function and glucose metabolism in the same subjects by positron emission tomography (PET) imaging approach, and investigate whether the correlation exists between D{sub 2} receptor and glucose metabolism. Twelve drug-naive adult males who met criteria for internet gaming disorder and 14 matched controls were studied with PET and {sup 11}C-N-methylspiperone ({sup 11}C-NMSP) to assess the availability of D{sub 2}/5-HT{sub 2A} receptors and with {sup 18}F-fluoro-D-glucose ({sup 18}F-FDG) to assess regional brain glucose metabolism, a marker of brain function. {sup 11}C-NMSP and {sup 18}F-FDG PET imaging data were acquired in the same individuals under both resting and internet gaming task states. In internet gaming disorder subjects, a significant decrease in glucose metabolism was observed in the prefrontal, temporal, and limbic systems. Dysregulation of D{sub 2} receptors was observed in the striatum, and was correlated to years of overuse. A low level of D{sub 2} receptors in the striatum was significantly associated with decreased glucose metabolism in the orbitofrontal cortex. For the first time, we report the evidence that D{sub 2} receptor level is significantly associated with glucose metabolism in the same individuals with internet gaming disorder, which indicates that D{sub 2}/5-HT{sub 2A} receptor-mediated dysregulation of the orbitofrontal cortex could underlie a mechanism for loss of control and compulsive behavior in internet gaming disorder subjects. (orig.)

  20. Metal complex-based templates and nanostructures for magnetic resonance/optical multimodal imaging agents

    NARCIS (Netherlands)

    Galindo Millan, J.J.

    2012-01-01

    In this thesis, new approaches directed towards simple and functional imaging agents (IAs) for magnetic resonance (MR) and fluorescence multimodal imaging are proposed. In Chapter 3, hybrid silver nanostructures (hAgNSs), grown using a polyamino carboxylic acid scaffold, namely 1,4,7,10-tetraaza-1-(

  1. An activatable, polarity dependent, dual-luminescent imaging agent with a long luminescence lifetime.

    Science.gov (United States)

    Rood, Marcus T M; Oikonomou, Maria; Buckle, Tessa; Raspe, Marcel; Urano, Yasuteru; Jalink, Kees; Velders, Aldrik H; van Leeuwen, Fijs W B

    2014-09-04

    In this proof-of-concept study, a new activatable imaging agent based on two luminophores and two different quenching mechanisms is reported. Both partial and total activation of the luminescence signal can be achieved, either in solution or in vitro. Bond cleavage makes the compound suitable for luminescence lifetime imaging.

  2. Image-matching as a medical diagnostic support tool (DST) for brain diseases in children.

    Science.gov (United States)

    Huang, H K; Nielsen, J F; Nelson, Marvin D; Liu, Lifeng

    2005-01-01

    Imaging-matching is an important research area in imaging informatics. We have developed and evaluated a novel diagnostic support tool (DST) based on medical image matching using MR brain images. The approach consists of two steps, database generation and image matching. The database contains pre-diagnosed MR brain images. As the images are added to the database, they are registered to the 3D Talairach coordinate system. In addition, regions of interests (ROI) are generated, and image-processing techniques are used to extract relevant image parameters related to the brain and diseases from the ROIs and from the entire MR image. The second step is to retrieve relevant information from the database by performing image matching. In this step, the physician first submits a query image. The DST computes the similarity between the query image and each of the images in the database, and then presents the most similar images to the user. Since the database contains pre-diagnosed images, the retrieved cases tend to contain relevant diagnostic information. To evaluate the usefulness of the DST in a clinical setting, pediatric brain diseases were used. The database contains 2500 pediatric patients between ages 0 and 18 with brain Magnetic Resonance (MR) images of known brain lesions. A testbed was established at the Children's Hospital Los Angeles (CHLA) for acquiring MR images from the PACS server of patients with known lesions. These images were matched against those in the DST pediatric brain MR database. An expert pediatric neuroradiologist evaluated the matched results. We found that in most cases, the image-matching method was able to quickly retrieve images with relevant diagnostic content. The evaluation method and results are given.

  3. PET imaging of neurogenic activity in the adult brain: Toward in vivo imaging of human neurogenesis.

    Science.gov (United States)

    Tamura, Yasuhisa; Kataoka, Yosky

    2017-01-01

    Neural stem cells are present in 2 neurogenic regions, the subventricular zone (SVZ) and the subgranular zone (SGZ) of the hippocampal dentate gyrus (DG), and continue to generate new neurons throughout life. Adult hippocampal neurogenesis is linked to a variety of psychiatric disorders such as depression and anxiety, and to the therapeutic effects of antidepressants, as well as learning and memory. In vivo imaging for hippocampal neurogenic activity may be used to diagnose psychiatric disorders and evaluate the therapeutic efficacy of antidepressants. However, these imaging techniques remain to be established until now. Recently, we established a quantitative positron emission tomography (PET) imaging technique for neurogenic activity in the adult brain with 3'-deoxy-3'-[(18)F]fluoro-L-thymidine ([(18)F]FLT) and probenecid, a drug transporter inhibitor in blood-brain barrier. Moreover, we showed that this PET imaging technique can monitor alterations in neurogenic activity in the hippocampus of adult rats with depression and following treatment with an antidepressant. This PET imaging method may assist in diagnosing depression and in monitoring the therapeutic efficacy of antidepressants. In this commentary, we discuss the possibility of in vivo PET imaging for neurogenic activity in adult non-human primates and humans.

  4. Imaging of Isotopically Enhanced Molecular Targeting Agents Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Quong, J N

    2004-02-19

    The goal of this project is to develop experimental and computational protocols to use SIMS to image the chemical composition of biological samples, focusing on optimizing sample preparation protocols and developing multivariate data analysis methods. Our results on sample preparation, molecular imaging, and multivariate analysis have been presented at several meeting abstracts (UCRL151797ABS, UCRL151797ABSREV1, UCRL151426ABS, UCRL201277, UCRL154757). A refereed paper describing our results for sample preparation and molecular imaging of various endogenous biomolecules as well as the mutagen PhIP has been accepted for publication (UCRL-JC-151797). We are also preparing two additional papers describing our multivariate analysis methods to analyze spectral data. As these papers have not been submitted, their content is included in this final report.

  5. One-step preparation of [(18)F]FPBM for PET imaging of serotonin transporter (SERT) in the brain.

    Science.gov (United States)

    Qiao, Hongwen; Zhang, Yan; Wu, Zehui; Zhu, Lin; Choi, Seok Rye; Ploessl, Karl; Kung, Hank F

    2016-08-01

    Serotonin transporters (SERT) in the brain play an important role in normal brain function. Selective serotonin reuptake inhibitors such as fluoxetine, sertraline, paroxetine, escitalopram, etc., specifically target SERT binding in the brain. Development of SERT imaging agents may be useful for studying the function of SERT by in vivo imaging. A one-step preparation of [(18)F]FPBM, 2-(2'-(dimethylamino)methyl)-4'-(3-([(18)F]fluoropropoxy)phenylthio)benzenamine, for positron emission tomography (PET) imaging of SERT binding in the brain was achieved. An active OTs intermediate, 9, was reacted with [(18)F]F(-)/K222 to produce [(18)F]FPBM in one step and in high radiochemical yield. This labeling reaction was evaluated and optimized under different temperatures, bases, solvents, and varying amounts of precursor 9. The radiolabeling reaction led to the desired [(18)F]FPBM in one step and the crude product was purified by HPLC purification to give no-carrier-added [(18)F]FPBM (radiochemical yield, 24-33%, decay corrected; radiochemical purity >99%). PET imaging studies in normal monkeys (n=4) showed fast, pronounced uptakes in the midbrain and thalamus, regions known to be rich in SERT binding sites. A displacement experiment with escitalopram (5mg/kg iv injection at 30min after [(18)F]FPBM injection) showed a rapid and complete reversal of SERT binding, suggesting that binding by [(18)F]FPBM was highly specific and reversible. A one-step radiolabeling method coupled with HPLC purification for preparation of [(18)F]FPBM was developed. Imaging studies suggest that it is feasible to use this method to prepare [(18)F]FPBM for in vivo PET imaging of SERT binding in the brain.

  6. EPR and DNP Properties of Certain Novel Single Electron Contrast Agents Intended for Oximetric Imaging

    DEFF Research Database (Denmark)

    Ardenkjær-Larsen, J. H.; Laursen, I; Leunbach, I.;

    1998-01-01

    Parameters of relevance to oximetry with Overhauser magnetic resonance imaging (OMRI) have been measured for three single electron contrast agents of the triphenylmethyl type. The single electron contrast agents are stable and water soluble. Magnetic resonance properties of the agents have been...... examined with electron paramagnetic resonance (EPR), nuclear magnetic resonance (NMR), and dynamic nuclear polarization (DNP) at 9.5 mT in water, isotonic saline, plasma, and blood at 23 and 37°C. The relaxivities of the agents are about 0.2–0.4 mM−1s−1and the DNP enhancements extrapolate close...... to the dipolar limit. The agents have a single, narrow EPR line, which is analyzed as a Voigt function. The linewidth is measured as a function of the agent concentration and the oxygen concentration. The concentration broadenings are about 1–3 μT/mM and the Lorentzian linewidths at infinite dilution are less...

  7. Imaging brain neuronal activity using functionalized magnetonanoparticles and MRI.

    Science.gov (United States)

    Akhtari, Massoud; Bragin, Anatol; Moats, Rex; Frew, Andrew; Mandelkern, Mark

    2012-10-01

    This study explored the use of non-radioactive 2-deoxy glucose (2DG)-labeled magnetonanoparticles (MNP) and magnetic resonance imaging (MRI) to detect functional activity during rest, peripheral stimulation, and epileptic seizures, in animal models. Non-radioactive 2DG was covalently attached to magnetonanoparticles composed of iron oxide and dextran and intravenous (tail) injections were performed. 2DG-MNP was injected in resting and stimulated naïve rodents and the subsequent MRI was compared to published (14)C-2DG autoradiography data. Reproducibility and statistical significance was established in one studied model. Negative contrast enhancement (NCE) in acute seizures and chronic models of epilepsy were investigated. MRI NCE due to 2DG-MNP particles was compared to that of plain (unconjugated) MNP in one animal. NCE due to 2DG-MNP particles at 3 T, which is approved for human use, was also investigated. Histology showed presence of MNP (following intravenous injection) in the brain tissues of resting naïve animal. 2DG-MNP intraparenchymal uptake was visible on MRI and histology. The locations of NCE agreed with published results of 2DG autoradiography in resting and stimulated animals and epileptic rats. Localization of epileptogenicity was confirmed by subsequent depth-electrode EEG (iEEG). Non-radioactive 2DG-MNP can cross the blood-brain barrier (BBB) and may accurately localize areas of increased activity. Although, this proof-of-principle study involves only a limited number of animals, and much more research and quantification are necessary to demonstrate that 2DG-MNP, or MNPs conjugated with other ligands, could eventually be used to image localized cerebral function with MRI in humans, this MNP-MRI approach is potentially applicable to the use of many bioactive molecules as ligands for imaging normal and abnormal localized cerebral functions.

  8. A quantitative MRI method for imaging blood-brain barrier leakage in experimental traumatic brain injury.

    Directory of Open Access Journals (Sweden)

    Wei Li

    Full Text Available Blood-brain barrier (BBB disruption is common following traumatic brain injury (TBI. Dynamic contrast enhanced (DCE MRI can longitudinally measure the transport coefficient Ktrans which reflects BBB permeability. Ktrans measurements however are not widely used in TBI research because it is generally considered to be noisy and possesses low spatial resolution. We improved spatiotemporal resolution and signal sensitivity of Ktrans MRI in rats by using a high-sensitivity surface transceiver coil. To overcome the signal drop off profile of the surface coil, a pre-scan module was used to map the flip angle (B1 field and magnetization (M0 distributions. A series of T1-weighted gradient echo images were acquired and fitted to the extended Kety model with reversible or irreversible leakage, and the best model was selected using F-statistics. We applied this method to study the rat brain one hour following controlled cortical impact (mild to moderate TBI, and observed clear depiction of the BBB damage around the impact regions, which matched that outlined by Evans Blue extravasation. Unlike the relatively uniform T2 contrast showing cerebral edema, Ktrans shows a pronounced heterogeneous spatial profile in and around the impact regions, displaying a nonlinear relationship with T2. This improved Ktrans MRI method is also compatible with the use of high-sensitivity surface coil and the high-contrast two-coil arterial spin-labeling method for cerebral blood flow measurement, enabling more comprehensive investigation of the pathophysiology in TBI.

  9. UNC-Emory Infant Atlases for Macaque Brain Image Analysis: Postnatal Brain Development through 12 Months

    Science.gov (United States)

    Shi, Yundi; Budin, Francois; Yapuncich, Eva; Rumple, Ashley; Young, Jeffrey T.; Payne, Christa; Zhang, Xiaodong; Hu, Xiaoping; Godfrey, Jodi; Howell, Brittany; Sanchez, Mar M.; Styner, Martin A.

    2017-01-01

    Computational anatomical atlases have shown to be of immense value in neuroimaging as they provide age appropriate reference spaces alongside ancillary anatomical information for automated analysis such as subcortical structural definitions, cortical parcellations or white fiber tract regions. Standard workflows in neuroimaging necessitate such atlases to be appropriately selected for the subject population of interest. This is especially of importance in early postnatal brain development, where rapid changes in brain shape and appearance render neuroimaging workflows sensitive to the appropriate atlas choice. We present here a set of novel computation atlases for structural MRI and Diffusion Tensor Imaging as crucial resource for the analysis of MRI data from non-human primate rhesus monkey (Macaca mulatta) data in early postnatal brain development. Forty socially-housed infant macaques were scanned longitudinally at ages 2 weeks, 3, 6, and 12 months in order to create cross-sectional structural and DTI atlases via unbiased atlas building at each of these ages. Probabilistic spatial prior definitions for the major tissue classes were trained on each atlas with expert manual segmentations. In this article we present the development and use of these atlases with publicly available tools, as well as the atlases themselves, which are publicly disseminated to the scientific community. PMID:28119564

  10. Molecular imaging agents for SPECT (and SPECT/CT)

    Energy Technology Data Exchange (ETDEWEB)

    Gnanasegaran, Gopinath [Guy' s and St Thomas' NHS Foundation Trust, Department of Nuclear Medicine, London (United Kingdom); Ballinger, James R. [Guy' s and St Thomas' NHS Foundation Trust, Department of Nuclear Medicine, London (United Kingdom); King' s College London, Division of Imaging Sciences and Biomedical Engineering, London (United Kingdom)

    2014-05-15

    The development of hybrid single photon emission computed tomography/computed tomography (SPECT/CT) cameras has increased the diagnostic value of many existing single photon radiopharmaceuticals. Precise anatomical localization of lesions greatly increases diagnostic confidence in bone imaging of the extremities, infection imaging, sentinel lymph node localization, and imaging in other areas. Accurate anatomical localization is particularly important prior to surgery, especially involving the parathyroid glands and sentinel lymph node procedures. SPECT/CT plays a role in characterization of lesions, particularly in bone scintigraphy and radioiodine imaging of metastatic thyroid cancer. In the development of novel tracers, SPECT/CT is particularly important in monitoring response to therapies that do not result in an early change in lesion size. Preclinical SPECT/CT devices, which actually have spatial resolution superior to PET/CT devices, have become essential in characterization of the biodistribution and tissue kinetics of novel tracers, allowing coregistration of serial studies within the same animals, which serves both to reduce biological variability and reduce the number of animals required. In conclusion, SPECT/CT increases the utility of existing radiopharmaceuticals and plays a pivotal role in the evaluation of novel tracers. (orig.)

  11. The Preparation and Application of Dendrimer Modified CdTe/CdS Near Infrared Quantum Dots for Brain Cancer Cells Imaging

    Directory of Open Access Journals (Sweden)

    Qingke Bai

    2015-11-01

    Full Text Available The most notable obstacle of brain cancer diagnosis is the inability of delivering imaging agents across the blood-brain barrier (BBB. Recently, quantum dots (QDs has been demonstrated as an ideal image agent for brain imaging due to their ultra-small size for crossing BBB. The plolyamidoamine dendrimers modified CdTe/CdS core/shell near-infrared (NIR region QDs was successfully synthesized in aqueous solution, and then was characterized by UV-vis absorption, photoluminescence (PL spectroscopy, dynamic light scattering (DLS, X-ray powder diffraction (XRD and high-resolution transmission electron microscopy (HR-TEM, etc. Our results reveal that the dendrimers modified CdTe/CdS QDs exhibits good water-dispersity and stable NIR fluorescence in various biological environments. In addition, this NIR QDs demonstrates a good biocompatibility and sensitive photoluminescence responses in brain tumor cell imaging. In a word, this type of dendrimers modified NIR CdTe/CdS QDs has huge potential applications in brain imaging.

  12. Combined blood pool and extracellular contrast agents for pediatric and young adult cardiovascular magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Joyce T. [Ann and Robert Lurie Children' s Hospital of Chicago, Division of Pediatric Cardiology, 225 E. Chicago Ave., Box 21, Chicago, IL (United States); Ann and Robert Lurie Children' s Hospital of Chicago, Department of Pediatrics, Chicago, IL (United States); Robinson, Joshua D. [Ann and Robert Lurie Children' s Hospital of Chicago, Division of Pediatric Cardiology, 225 E. Chicago Ave., Box 21, Chicago, IL (United States); Ann and Robert Lurie Children' s Hospital of Chicago, Department of Pediatrics, Chicago, IL (United States); Northwestern University, Department of Radiology, Feinberg School of Medicine, Chicago, IL (United States); Deng, Jie [Northwestern University, Department of Radiology, Feinberg School of Medicine, Chicago, IL (United States); Ann and Robert Lurie Children' s Hospital of Chicago, Department of Medical Imaging, Chicago, IL (United States); Rigsby, Cynthia K. [Ann and Robert Lurie Children' s Hospital of Chicago, Department of Pediatrics, Chicago, IL (United States); Northwestern University, Department of Radiology, Feinberg School of Medicine, Chicago, IL (United States); Ann and Robert Lurie Children' s Hospital of Chicago, Department of Medical Imaging, Chicago, IL (United States)

    2016-12-15

    A comprehensive cardiac magnetic resonance (cardiac MR) study including both late gadolinium enhancement (LGE) and MR angiography may be indicated for patients with a history of acquired or congenital heart disease. To study the novel use of an extracellular agent for assessment of LGE combined with a blood pool contrast agent for detailed MR angiography evaluation to yield a comprehensive cardiac MR study in these patients. We reviewed clinical cardiac MR studies utilizing extracellular and blood pool contrast agents and noted demographics, clinical data and adverse events. We rated LGE image quality and MR angiography image quality for each vascular segment and calculated inter-rater variability. We also quantified contrast-to-noise ratio (CNR). Thirty-three patients (mean age 13.9 ± 3 years) received an extracellular contrast agent (10 gadobenate dimeglumine, 23 gadopentetate dimeglumine) and blood pool contrast agent (33 gadofosveset trisodium). No adverse events were reported. MRI indications included Kawasaki disease (8), cardiomyopathy and coronary anatomy (15), repaired congenital heart disease (8), and other (2). Mean LGE quality was 2.6 ± 0.6 with 97% diagnostic imaging. LGE quality did not vary by type of contrast agent given (P = 0.07). Mean MR angiography quality score was 4.7 ± 0.6, with high inter-rater agreement (k = 0.6-0.8, P < 0.002). MR angiography quality did not vary by type of contrast agent used (P = 0.6). Cardiac MR studies utilizing both extracellular and blood pool contrast agents are feasible and safe and provide excellent-quality LGE and MR angiography images. The use of two contrast agents allows for a comprehensive assessment of both myocardial viability and vascular anatomy during the same exam. (orig.)

  13. Regional distribution of halopemide, a new psychotropic agent, in the rat brain at different time intervals and after chronic administration

    NARCIS (Netherlands)

    Loonen, A.J.M.; Van Wijngaarden, I.; Janssen, P.A.J.; Soudijn, W.

    1979-01-01

    Only a very small amount of halopemide, a new psychotropic agent, structurally related to the butyrophenones, but with a different pharmacological and clinical profile, penetrates into the rat brain. The maximum concentration is reached between 1 and 2 hours after injection. Halopemide is evenly dis

  14. Classification of CT brain images based on deep learning networks.

    Science.gov (United States)

    Gao, Xiaohong W; Hui, Rui; Tian, Zengmin

    2017-01-01

    While computerised tomography (CT) may have been the first imaging tool to study human brain, it has not yet been implemented into clinical decision making process for diagnosis of Alzheimer's disease (AD). On the other hand, with the nature of being prevalent, inexpensive and non-invasive, CT does present diagnostic features of AD to a great extent. This study explores the significance and impact on the application of the burgeoning deep learning techniques to the task of classification of CT brain images, in particular utilising convolutional neural network (CNN), aiming at providing supplementary information for the early diagnosis of Alzheimer's disease. Towards this end, three categories of CT images (N = 285) are clustered into three groups, which are AD, lesion (e.g. tumour) and normal ageing. In addition, considering the characteristics of this collection with larger thickness along the direction of depth (z) (~3-5 mm), an advanced CNN architecture is established integrating both 2D and 3D CNN networks. The fusion of the two CNN networks is subsequently coordinated based on the average of Softmax scores obtained from both networks consolidating 2D images along spatial axial directions and 3D segmented blocks respectively. As a result, the classification accuracy rates rendered by this elaborated CNN architecture are 85.2%, 80% and 95.3% for classes of AD, lesion and normal respectively with an average of 87.6%. Additionally, this improved CNN network appears to outperform the others when in comparison with 2D version only of CNN network as well as a number of state of the art hand-crafted approaches. As a result, these approaches deliver accuracy rates in percentage of 86.3, 85.6 ± 1.10, 86.3 ± 1.04, 85.2 ± 1.60, 83.1 ± 0.35 for 2D CNN, 2D SIFT, 2D KAZE, 3D SIFT and 3D KAZE respectively. The two major contributions of the paper constitute a new 3-D approach while applying deep learning technique to extract signature information

  15. The iconographic brain. A critical philosophical inquiry into (the resistance of) the image

    Science.gov (United States)

    De Vos, Jan

    2014-01-01

    The brain image plays a central role in contemporary image culture and, in turn, (co)constructs contemporary forms of subjectivity. The central aim of this paper is to probe the unmistakably potent interpellative power of brain images by delving into the power of imaging and the power of the image itself. This is not without relevance for the neurosciences, inasmuch as these do not take place in a vacuum; hence the importance of inquiring into the status of the image within scientific culture and science itself. I will mount a critical philosophical investigation of the brain qua image, focusing on the issue of mapping the mental onto the brain and how, in turn, the brain image plays a pivotal role in processes of subjectivation. Hereto, I draw upon Science & Technology Studies, juxtaposed with culture and ideology critique and theories of image culture. The first section sets out from Althusser's concept of interpellation, linking ideology to subjectivity. Doing so allows to spell out the central question of the paper: what could serve as the basis for a critical approach, or, where can a locus of resistance be found? In the second section, drawing predominantly on Baudrillard, I delve into the dimension of virtuality as this is opened up by brain image culture. This leads to the question of whether the digital brain must be opposed to old analog psychology: is it the psyche which resists? This issue is taken up in the third section which, ultimately, concludes that the psychological is not the requisite locus of resistance. The fourth section proceeds to delineate how the brain image is constructed from what I call the data-gaze (the claim that brain data are always already visual). In the final section, I discuss how an engagement with theories of iconology affords a critical understanding of the interpellative force of the brain image, which culminates in the somewhat unexpected claim that the sought after resistance lies in the very status of the image itself

  16. The iconographic brain. A critical philosophical inquiry into (the resistance of) the image.

    Science.gov (United States)

    De Vos, Jan

    2014-01-01

    The brain image plays a central role in contemporary image culture and, in turn, (co)constructs contemporary forms of subjectivity. The central aim of this paper is to probe the unmistakably potent interpellative power of brain images by delving into the power of imaging and the power of the image itself. This is not without relevance for the neurosciences, inasmuch as these do not take place in a vacuum; hence the importance of inquiring into the status of the image within scientific culture and science itself. I will mount a critical philosophical investigation of the brain qua image, focusing on the issue of mapping the mental onto the brain and how, in turn, the brain image plays a pivotal role in processes of subjectivation. Hereto, I draw upon Science & Technology Studies, juxtaposed with culture and ideology critique and theories of image culture. The first section sets out from Althusser's concept of interpellation, linking ideology to subjectivity. Doing so allows to spell out the central question of the paper: what could serve as the basis for a critical approach, or, where can a locus of resistance be found? In the second section, drawing predominantly on Baudrillard, I delve into the dimension of virtuality as this is opened up by brain image culture. This leads to the question of whether the digital brain must be opposed to old analog psychology: is it the psyche which resists? This issue is taken up in the third section which, ultimately, concludes that the psychological is not the requisite locus of resistance. The fourth section proceeds to delineate how the brain image is constructed from what I call the data-gaze (the claim that brain data are always already visual). In the final section, I discuss how an engagement with theories of iconology affords a critical understanding of the interpellative force of the brain image, which culminates in the somewhat unexpected claim that the sought after resistance lies in the very status of the image itself.

  17. AN IMPROVED TECHNIQUE FOR IDENTIFICATION AND CLASSIFICATION OF BRAIN DISORDER FROM MRI BRAIN IMAGE

    Directory of Open Access Journals (Sweden)

    Finitha Joseph

    2015-11-01

    Full Text Available Medical image processing is developing recently due to its wide applications. An efficient MRI image segmentation is needed at present. In this paper, MRI brain segmentation is done by Semi supervised learning which does not require pathology modelling and, thus, allows high degree of automation. In abnormality detection, a vector is characterized as anomalous if it does not comply with the probability distribution obtained from normal data. The estimation of the probability density function, however, is usually not feasible due to large data dimensionality. In order to overcome this challenge, we treat every image as a network of locally coherent image partitions (overlapping blocks. We formulate and maximize a strictly concave likelihood function estimating abnormality for each partition and fuse the local estimates into a globally optimal estimate that satisfies the consistency constraints, based on a distributed estimation algorithm. After this features are extracted by Gray-Level Co-occurrence Matrices (GLCM algorithm and those features are given to Particle Spam Optimization (PSO and finally classification is done by using Library Support Vector Machine (LIBSVM.Thus results are evaluated and proved its efficiency using accuracy.

  18. A dual function theranostic agent for near-infrared photoacoustic imaging and photothermal therapy

    Science.gov (United States)

    Upputuri, Paul Kumar; Huang, Shuo; Wang, Mingfeng; Pramanik, Manojit

    2016-03-01

    Theranostic, defined as combining diagnostic and therapeutic agents, has attracted more attention in biomedical application. It is essential to monitor diseased tissue before treatment. Photothermal therapy (PTT) is a promising treatment of cancer tissue due to minimal invasion, unharmful to normal tissue and high efficiency. Photoacoustic tomography (PAT) is a hybrid nonionizing biomedical imaging modality that combines rich optical contrast and high ultrasonic resolution in a single imaging modality. The near infra-red (NIR) wavelengths, usually used in PAT, can provide deep penetration at the expense of reduced contrast, as the blood absorption drops in the NIR range. Exogenous contrast agents with strong absorption in the NIR wavelength range can enhance the photoacoustic imaging contrast as well as imaging depth. Most theranostic agents incorporating PAT and PTT are inorganic nanomaterials that suffer from poor biocompatibility and biodegradability. Herein, we present an benzo[1,2-c;4,5-c'] bis[1,2,5] thiadiazole (BBT), based theranostic agent which not only acts as photoacoustic contrast agent but also a photothermal therapy agent. Experiments were performed on animal blood and organic nanoparticles embedded in a chicken breast tissue using PAT imaging system at ~803 nm wavelengths. Almost ten time contrast enhancement was observed from the nanoparticle in suspension. More than 6.5 time PA signal enhancement was observed in tissue at 3 cm depth. HeLa cell lines was used to test photothermal effect showing 90% cells were killed after 10 min laser irradiation. Our results indicate that the BBT - based naoparticles are promising theranostic agents for PAT imaging and cancer treatment by photothermal therapy.

  19. SU-E-QI-21: Iodinated Contrast Agent Time Course In Human Brain Metastasis: A Study For Stereotactic Synchrotron Radiotherapy Clinical Trials

    Energy Technology Data Exchange (ETDEWEB)

    Obeid, L; Esteve, F; Adam, J [Grenoble Institut des Neurosciences, La Tronche, Isere (France); Tessier, A; Balosso, J [Centre Hospitalier Universitaire, La Tronche, Isere (France)

    2014-06-15

    Purpose: Synchrotron stereotactic radiotherapy (SSRT) is an innovative treatment combining the selective accumulation of heavy elements in tumors with stereotactic irradiations using monochromatic medium energy x-rays from a synchrotron source. Phase I/II clinical trials on brain metastasis are underway using venous infusion of iodinated contrast agents. The radiation dose enhancement depends on the amount of iodine in the tumor and its time course. In the present study, the reproducibility of iodine concentrations between the CT planning scan day (Day 0) and the treatment day (Day 10) was assessed in order to predict dose errors. Methods: For each of days 0 and 10, three patients received a biphasic intravenous injection of iodinated contrast agent (40 ml, 4 ml/s, followed by 160 ml, 0.5 ml/s) in order to ensure stable intra-tumoral amounts of iodine during the treatment. Two volumetric CT scans (before and after iodine injection) and a multi-slice dynamic CT of the brain were performed using conventional radiotherapy CT (Day 0) or quantitative synchrotron radiation CT (Day 10). A 3D rigid registration was processed between images. The absolute and relative differences of absolute iodine concentrations and their corresponding dose errors were evaluated in the GTV and PTV used for treatment planning. Results: The differences in iodine concentrations remained within the standard deviation limits. The 3D absolute differences followed a normal distribution centered at zero mg/ml with a variance (∼1 mg/ml) which is related to the image noise. Conclusion: The results suggest that dose errors depend only on the image noise. This study shows that stable amounts of iodine are achievable in brain metastasis for SSRT treatment in a 10 days interval.

  20. Synthesis and biodistribution of a new 99mTc nitrido complex as a potential myocardial and cerebral imaging agent.

    Science.gov (United States)

    Zhang, JunBo; Wang, XueBin; Li, ChunYun

    2002-06-01

    The bis(N-methyl, N-cyclohexyl dithiocarbamato) nitrido technetium-99m complex [99mTcN(MECHDTC)2] (MECHDTC: N-methyl, N-cyclohexyl dithiocarbamato) has been synthesized through a ligand-exchange reaction. The two-step procedure consisted of an initial reaction of 99mTcO4- with succinic dihydrazide in the presence of stannous chloride as reducing agent and propylenediamine tetraacetic acid as complexant, and successive addition of sodium salt of N-methyl, N-cyclohexyl dithiocarbamate. The radiochemical purity of the complex was over 90%, as measured by thin layer chromatography. No decomposition of the complex at room temperature was observed over a period of 6 h. Its partition coefficient indicated that it was a lipophilic complex. The electrophoresis results showed that the complex was neutral. Biodistribution in mice showed that the complex accumulated in the heart and brain with high uptake. The heart/blood, heart/lung and brain/blood ratios were 5.55, 2.11 and 1.10, respectively, at 30 min post-injection, suggesting that this compound is a potential myocardial and cerebral imaging agent.

  1. The Multimodal Brain Tumor Image Segmentation Benchmark (BRATS).

    Science.gov (United States)

    Menze, Bjoern H; Jakab, Andras; Bauer, Stefan; Kalpathy-Cramer, Jayashree; Farahani, Keyvan; Kirby, Justin; Burren, Yuliya; Porz, Nicole; Slotboom, Johannes; Wiest, Roland; Lanczi, Levente; Gerstner, Elizabeth; Weber, Marc-André; Arbel, Tal; Avants, Brian B; Ayache, Nicholas; Buendia, Patricia; Collins, D Louis; Cordier, Nicolas; Corso, Jason J; Criminisi, Antonio; Das, Tilak; Delingette, Hervé; Demiralp, Çağatay; Durst, Christopher R; Dojat, Michel; Doyle, Senan; Festa, Joana; Forbes, Florence; Geremia, Ezequiel; Glocker, Ben; Golland, Polina; Guo, Xiaotao; Hamamci, Andac; Iftekharuddin, Khan M; Jena, Raj; John, Nigel M; Konukoglu, Ender; Lashkari, Danial; Mariz, José Antonió; Meier, Raphael; Pereira, Sérgio; Precup, Doina; Price, Stephen J; Raviv, Tammy Riklin; Reza, Syed M S; Ryan, Michael; Sarikaya, Duygu; Schwartz, Lawrence; Shin, Hoo-Chang; Shotton, Jamie; Silva, Carlos A; Sousa, Nuno; Subbanna, Nagesh K; Szekely, Gabor; Taylor, Thomas J; Thomas, Owen M; Tustison, Nicholas J; Unal, Gozde; Vasseur, Flor; Wintermark, Max; Ye, Dong Hye; Zhao, Liang; Zhao, Binsheng; Zikic, Darko; Prastawa, Marcel; Reyes, Mauricio; Van Leemput, Koen

    2015-10-01

    In this paper we report the set-up and results of the Multimodal Brain Tumor Image Segmentation Benchmark (BRATS) organized in conjunction with the MICCAI 2012 and 2013 conferences. Twenty state-of-the-art tumor segmentation algorithms were applied to a set of 65 multi-contrast MR scans of low- and high-grade glioma patients-manually annotated by up to four raters-and to 65 comparable scans generated using tumor image simulation software. Quantitative evaluations revealed considerable disagreement between the human raters in segmenting various tumor sub-regions (Dice scores in the range 74%-85%), illustrating the difficulty of this task. We found that different algorithms worked best for different sub-regions (reaching performance comparable to human inter-rater variability), but that no single algorithm ranked in the top for all sub-regions simultaneously. Fusing several good algorithms using a hierarchical majority vote yielded segmentations that consistently ranked above all individual algorithms, indicating remaining opportunities for further methodological improvements. The BRATS image data and manual annotations continue to be publicly available through an online evaluation system as an ongoing benchmarking resource.

  2. Deploying swarm intelligence in medical imaging identifying metastasis, micro-calcifications and brain image segmentation.

    Science.gov (United States)

    al-Rifaie, Mohammad Majid; Aber, Ahmed; Hemanth, Duraiswamy Jude

    2015-12-01

    This study proposes an umbrella deployment of swarm intelligence algorithm, such as stochastic diffusion search for medical imaging applications. After summarising the results of some previous works which shows how the algorithm assists in the identification of metastasis in bone scans and microcalcifications on mammographs, for the first time, the use of the algorithm in assessing the CT images of the aorta is demonstrated along with its performance in detecting the nasogastric tube in chest X-ray. The swarm intelligence algorithm presented in this study is adapted to address these particular tasks and its functionality is investigated by running the swarms on sample CT images and X-rays whose status have been determined by senior radiologists. In addition, a hybrid swarm intelligence-learning vector quantisation (LVQ) approach is proposed in the context of magnetic resonance (MR) brain image segmentation. The particle swarm optimisation is used to train the LVQ which eliminates the iteration-dependent nature of LVQ. The proposed methodology is used to detect the tumour regions in the abnormal MR brain images.

  3. AN ARTIFICIAL FISH SWARM OPTIMIZED FUZZY MRI IMAGE SEGMENTATION APPROACH FOR IMPROVING IDENTIFICATION OF BRAIN TUMOUR

    OpenAIRE

    Jagadeesan, R; S.N. Sivanandam

    2013-01-01

    In image processing, it is difficult to detect the abnormalities in brain especially in MRI brain images. Also the tumor segmentation from MRI image data is an important; however it is time consumingwhile carried out by medical specialists. A lot of methods have been proposed to solve MR images problems, quite difficult to develop an automated recognition system which could process on a large information of patient and provide a correct estimation. Hence enhanced k-means and fuzzy c-means wit...

  4. Rapid-releasing of HI-6 via brain-targeted mesoporous silica nanoparticles for nerve agent detoxification

    Science.gov (United States)

    Yang, Jun; Fan, Lixue; Wang, Feijian; Luo, Yuan; Sui, Xin; Li, Wanhua; Zhang, Xiaohong; Wang, Yongan

    2016-05-01

    The toxic nerve agent (NA) soman is the most toxic artificially synthesized compound that can rapidly penetrate into the brain and irreversibly inhibit acetylcholinesterase (AChE) activity, leading to immediate death. However, there are currently few brain-targeted nanodrugs that can treat acute chemical brain poisoning owing to the limited drug-releasing speed. The present study investigated the effectiveness of a nanodrug against NA toxicity that has high blood-brain barrier penetration and is capable of rapid drug release. Transferrin-modified mesoporous silica nanoparticles (TF-MSNs) were conjugated with the known AChE reactivator HI-6. This nanodrug rapidly penetrated the blood-brain barrier in zebrafish and mice and restored cerebral AChE activity via the released HI-6, preventing the brain damage caused by soman poisoning and increasing the survival rate in mice. Furthermore, there was no toxicity associated with the MSNs in mice or rats. These results demonstrate that TF-MSNs loaded with HI-6 represent the most effective antidote against NA poisoning by soman reported to date, and suggest that MSNs are a safe alternative to conventional drugs and an optimal nanocarrier for treating brain poisoning, which requires acute pulse cerebral administration.The toxic nerve agent (NA) soman is the most toxic artificially synthesized compound that can rapidly penetrate into the brain and irreversibly inhibit acetylcholinesterase (AChE) activity, leading to immediate death. However, there are currently few brain-targeted nanodrugs that can treat acute chemical brain poisoning owing to the limited drug-releasing speed. The present study investigated the effectiveness of a nanodrug against NA toxicity that has high blood-brain barrier penetration and is capable of rapid drug release. Transferrin-modified mesoporous silica nanoparticles (TF-MSNs) were conjugated with the known AChE reactivator HI-6. This nanodrug rapidly penetrated the blood-brain barrier in zebrafish and

  5. Regulation of P-glycoprotein expression in brain capillaries in Huntington's disease and its impact on brain availability of antipsychotic agents risperidone and paliperidone.

    Science.gov (United States)

    Kao, Yu-Han; Chern, Yijuang; Yang, Hui-Ting; Chen, Hui-Mei; Lin, Chun-Jung

    2016-08-01

    Huntington's disease (HD) is a neurodegenerative disease marked by an expanded polyglutamine (polyQ) tract on the huntingtin (HTT) protein that may cause transcriptional dysfunction. This study aimed to investigate the regulation and function of P-glycoprotein, an important efflux transporter, in brain capillaries in HD. The results showed that, compared with the littermate controls, R6/2 HD transgenic mice with the human mutant HTT gene had higher levels of P-glycoprotein mRNA and protein and enhanced NF-κB activity in their brain capillaries. Higher P-glycoprotein expression was also observed in the brain capillaries of human HD patients. Consistent with this enhanced P-glycoprotein expression, brain extracellular levels and brain-to-plasma ratios of the antipsychotic agents risperidone and paliperidone were significantly lower in R6/2 mice than in their littermate controls. Exogenous expression of human mutant HTT protein with expanded polyQ (mHTT-109Q) in HEK293T cells enhanced the levels of P-glycoprotein transcripts and NF-κB activity compared with cells expressing normal HTT-25Q. Treatment with the IKK inhibitor, BMS-345541, decreased P-glycoprotein mRNA level in cells transfected with mHTT-109Q or normal HTT-25Q In conclusion, mutant HTT altered the expression of P-glycoprotein through the NF-κB pathway in brain capillaries in HD and markedly affected the availability of P-glycoprotein substrates in the brain.

  6. Multimodal imaging of the self-regulating developing brain.

    Science.gov (United States)

    Fjell, Anders M; Walhovd, Kristine Beate; Brown, Timothy T; Kuperman, Joshua M; Chung, Yoonho; Hagler, Donald J; Venkatraman, Vijay; Roddey, J Cooper; Erhart, Matthew; McCabe, Connor; Akshoomoff, Natacha; Amaral, David G; Bloss, Cinnamon S; Libiger, Ondrej; Darst, Burcu F; Schork, Nicholas J; Casey, B J; Chang, Linda; Ernst, Thomas M; Gruen, Jeffrey R; Kaufmann, Walter E; Kenet, Tal; Frazier, Jean; Murray, Sarah S; Sowell, Elizabeth R; van Zijl, Peter; Mostofsky, Stewart; Jernigan, Terry L; Dale, Anders M

    2012-11-27

    Self-regulation refers to the ability to control behavior, cognition, and emotions, and self-regulation failure is related to a range of neuropsychiatric problems. It is poorly understood how structural maturation of the brain brings about the gradual improvement in self-regulation during childhood. In a large-scale multicenter effort, 735 children (4-21 y) underwent structural MRI for quantification of cortical thickness and surface area and diffusion tensor imaging for quantification of the quality of major fiber connections. Brain development was related to a standardized measure of cognitive control (the flanker task from the National Institutes of Health Toolbox), a critical component of self-regulation. Ability to inhibit responses and impose cognitive control increased rapidly during preteen years. Surface area of the anterior cingulate cortex accounted for a significant proportion of the variance in cognitive performance. This finding is intriguing, because characteristics of the anterior cingulum are shown to be related to impulse, attention, and executive problems in neurodevelopmental disorders, indicating a neural foundation for self-regulation abilities along a continuum from normality to pathology. The relationship was strongest in the younger children. Properties of large-fiber connections added to the picture by explaining additional variance in cognitive control. Although cognitive control was related to surface area of the anterior cingulate independently of basic processes of mental speed, the relationship between white matter quality and cognitive control could be fully accounted for by speed. The results underscore the need for integration of different aspects of brain maturation to understand the foundations of cognitive development.

  7. Prognostic Value of Brain Diffusion Weighted Imaging After Cardiac Arrest

    Science.gov (United States)

    Wijman, Christine A.C.; Mlynash, Michael; Caulfield, Anna Finley; Hsia, Amie W.; Eyngorn, Irina; Bammer, Roland; Fischbein, Nancy; Albers, Gregory W.; Moseley, Michael

    2009-01-01

    Objective Outcome prediction is challenging in comatose post-cardiac arrest survivors. We assessed the feasibility and prognostic utility of brain diffusion-weighted MRI (DWI) during the first week. Methods Consecutive comatose post-cardiac arrest patients were prospectively enrolled. MRI data of patients who met predefined specific prognostic criteria were used to determine distinguishing ADC thresholds. Group 1: death at 6 months and absent motor response or absent pupillary reflexes or bilateral absent cortical responses at 72 hours, or vegetative at 1 month. Group 2A: Glasgow outcome scale (GOS) score of 4 or 5 at 6 months. Group 2B: GOS of 3 at 6 months. The percentage of voxels below different apparent diffusion coefficient (ADC) thresholds was calculated at 50 × 10−6 mm2/sec intervals. Results Overall, 86% of patients underwent MR imaging. Fifty-one patients with 62 brain MRIs were included in the analyses. Forty patients met the specific prognostic criteria. The percentage of brain volume with an ADC value below 650–700 × 10−6 mm2/sec best differentiated between group 1 and groups 2A and 2B combined (p<0.001), while the 400–450 × 10−6 mm2/sec threshold best differentiated between groups 2A and 2B (p=0.003). The ideal time window for prognostication using DWI was between 49 to 108 hours after the arrest. When comparing MRI in this time window with the 72 hour neurological examination MRI improved the sensitivity for predicting poor outcome by 38% while maintaining 100% specificity (p=0.021). Interpretation Quantitative DWI in comatose post-cardiac arrest survivors holds great promise as a prognostic adjunct. PMID:19399889

  8. Synthesis and characterization of ethosomal contrast agents containing iodine for computed tomography (CT) imaging applications.

    Science.gov (United States)

    Shin, Hanjin; Cho, Young-Min; Lee, Kangtaek; Lee, Chang-Ha; Choi, Byoung Wook; Kim, Bumsang

    2014-06-01

    As a first step in the development of novel liver-specific contrast agents using ethosomes for computed tomography (CT) imaging applications, we entrapped iodine within ethosomes, which are phospholipid vesicular carriers containing relatively high alcohol concentrations, synthesized using several types of alcohol, such as methanol, ethanol, and propanol. The iodine containing ethosomes that were prepared using methanol showed the smallest vesicle size (392 nm) and the highest CT density (1107 HU). The incorporation of cholesterol into the ethosomal contrast agents improved the stability of the ethosomes but made the vesicle size large. The ethosomal contrast agents were taken up well by macrophage cells and showed no cellular toxicity. The results demonstrated that ethosomes containing iodine, as prepared in this study, have potential as contrast agents for applications in CT imaging.

  9. Imaging Plasmodium immunobiology in the liver, brain, and lung.

    Science.gov (United States)

    Frevert, Ute; Nacer, Adéla; Cabrera, Mynthia; Movila, Alexandru; Leberl, Maike

    2014-02-01

    Plasmodium falciparum malaria is responsible for the deaths of over half a million African children annually. Until a decade ago, dynamic analysis of the malaria parasite was limited to in vitro systems with the typical limitations associated with 2D monocultures or entirely artificial surfaces. Due to extremely low parasite densities, the liver was considered a black box in terms of Plasmodium sporozoite invasion, liver stage development, and merozoite release into the blood. Further, nothing was known about the behavior of blood stage parasites in organs such as the brain where clinical signs manifest and the ensuing immune response of the host that may ultimately result in a fatal outcome. The advent of fluorescent parasites, advances in imaging technology, and availability of an ever-increasing number of cellular and molecular probes have helped illuminate many steps along the pathogenetic cascade of this deadly tropical parasite.

  10. Unsupervised fuzzy segmentation of 3D magnetic resonance brain images

    Science.gov (United States)

    Velthuizen, Robert P.; Hall, Lawrence O.; Clarke, Laurence P.; Bensaid, Amine M.; Arrington, J. A.; Silbiger, Martin L.

    1993-07-01

    Unsupervised fuzzy methods are proposed for segmentation of 3D Magnetic Resonance images of the brain. Fuzzy c-means (FCM) has shown promising results for segmentation of single slices. FCM has been investigated for volume segmentations, both by combining results of single slices and by segmenting the full volume. Different strategies and initializations have been tried. In particular, two approaches have been used: (1) a method by which, iteratively, the furthest sample is split off to form a new cluster center, and (2) the traditional FCM in which the membership grade matrix is initialized in some way. Results have been compared with volume segmentations by k-means and with two supervised methods, k-nearest neighbors and region growing. Results of individual segmentations are presented as well as comparisons on the application of the different methods to a number of tumor patient data sets.

  11. Multislice CT brain image registration for perfusion studies

    Science.gov (United States)

    Lin, Zhong Min; Pohlman, Scott; Chandra, Shalabh

    2002-04-01

    During the last several years perfusion CT techniques have been developed as an effective technique for clinically evaluating cerebral hemodynamics. Perfusion CT techniques are capable of measurings functional parameters such as tissue perfusion, blood flow, blood volume, and mean transit time and are commonly used to evaluate stroke patients. However, the quality of functional images of the brain frequently suffers from patient head motion. Because the time window for an effective treatment of stroke patient is narrow, a fast motion correction is required. The purpose of the paper is to present a fast and accurate registration technique for motion correction of multi-slice CT and to demonstrate the effects of the registration on perfusion calculation.

  12. Distributed representations in memory: insights from functional brain imaging.

    Science.gov (United States)

    Rissman, Jesse; Wagner, Anthony D

    2012-01-01

    Forging new memories for facts and events, holding critical details in mind on a moment-to-moment basis, and retrieving knowledge in the service of current goals all depend on a complex interplay between neural ensembles throughout the brain. Over the past decade, researchers have increasingly utilized powerful analytical tools (e.g., multivoxel pattern analysis) to decode the information represented within distributed functional magnetic resonance imaging activity patterns. In this review, we discuss how these methods can sensitively index neural representations of perceptual and semantic content and how leverage on the engagement of distributed representations provides unique insights into distinct aspects of memory-guided behavior. We emphasize that, in addition to characterizing the contents of memories, analyses of distributed patterns shed light on the processes that influence how information is encoded, maintained, or retrieved, and thus inform memory theory. We conclude by highlighting open questions about memory that can be addressed through distributed pattern analyses.

  13. Memory Networks in Tinnitus: A Functional Brain Image Study

    Science.gov (United States)

    Laureano, Maura Regina; Onishi, Ektor Tsuneo; Bressan, Rodrigo Affonseca; Castiglioni, Mario Luiz Vieira; Batista, Ilza Rosa; Reis, Marilia Alves; Garcia, Michele Vargas; de Andrade, Adriana Neves; de Almeida, Roberta Ribeiro; Garrido, Griselda J.; Jackowski, Andrea Parolin

    2014-01-01

    Tinnitus is characterized by the perception of sound in the absence of an external auditory stimulus. The network connectivity of auditory and non-auditory brain structures associated with emotion, memory and attention are functionally altered in debilitating tinnitus. Current studies suggest that tinnitus results from neuroplastic changes in the frontal and limbic temporal regions. The objective of this study was to use Single-Photon Emission Computed Tomography (SPECT) to evaluate changes in the cerebral blood flow in tinnitus patients with normal hearing compared with healthy controls. Methods: Twenty tinnitus patients with normal hearing and 17 healthy controls, matched for sex, age and years of education, were subjected to Single Photon Emission Computed Tomography using the radiotracer ethylenedicysteine diethyl ester, labeled with Technetium 99 m (99 mTc-ECD SPECT). The severity of tinnitus was assessed using the “Tinnitus Handicap Inventory” (THI). The images were processed and analyzed using “Statistical Parametric Mapping” (SPM8). Results: A significant increase in cerebral perfusion in the left parahippocampal gyrus (pFWE <0.05) was observed in patients with tinnitus compared with healthy controls. The average total THI score was 50.8+18.24, classified as moderate tinnitus. Conclusion: It was possible to identify significant changes in the limbic system of the brain perfusion in tinnitus patients with normal hearing, suggesting that central mechanisms, not specific to the auditory pathway, are involved in the pathophysiology of symptoms, even in the absence of clinically diagnosed peripheral changes. PMID:24516567

  14. Functional brain imaging predicts public health campaign success.

    Science.gov (United States)

    Falk, Emily B; O'Donnell, Matthew Brook; Tompson, Steven; Gonzalez, Richard; Dal Cin, Sonya; Strecher, Victor; Cummings, Kenneth Michael; An, Lawrence

    2016-02-01

    Mass media can powerfully affect health decision-making. Pre-testing through focus groups or surveys is a standard, though inconsistent, predictor of effectiveness. Converging evidence demonstrates that activity within brain systems associated with self-related processing can predict individual behavior in response to health messages. Preliminary evidence also suggests that neural activity in small groups can forecast population-level campaign outcomes. Less is known about the psychological processes that link neural activity and population-level outcomes, or how these predictions are affected by message content. We exposed 50 smokers to antismoking messages and used their aggregated neural activity within a 'self-localizer' defined region of medial prefrontal cortex to predict the success of the same campaign messages at the population level (n = 400,000 emails). Results demonstrate that: (i) independently localized neural activity during health message exposure complements existing self-report data in predicting population-level campaign responses (model combined R(2) up to 0.65) and (ii) this relationship depends on message content-self-related neural processing predicts outcomes in response to strong negative arguments against smoking and not in response to compositionally similar neutral images. These data advance understanding of the psychological link between brain and large-scale behavior and may aid the construction of more effective media health campaigns.

  15. Hypnosis and imaging of the living human brain.

    Science.gov (United States)

    Landry, Mathieu; Raz, Amir

    2015-01-01

    Over more than two decades, studies using imaging techniques of the living human brain have begun to explore the neural correlates of hypnosis. The collective findings provide a gripping, albeit preliminary, account of the underlying neurobiological mechanisms involved in hypnotic phenomena. While substantial advances lend support to different hypotheses pertaining to hypnotic modulation of attention, control, and monitoring processes, the complex interactions among the many mediating variables largely hinder our ability to isolate robust commonalities across studies. The present account presents a critical integrative synthesis of neuroimaging studies targeting hypnosis as a function of suggestion. Specifically, hypnotic induction without task-specific suggestion is examined, as well as suggestions concerning sensation and perception, memory, and ideomotor response. The importance of carefully designed experiments is highlighted to better tease apart the neural correlates that subserve hypnotic phenomena. Moreover, converging findings intimate that hypnotic suggestions seem to induce specific neural patterns. These observations propose that suggestions may have the ability to target focal brain networks. Drawing on evidence spanning several technological modalities, neuroimaging studies of hypnosis pave the road to a more scientific understanding of a dramatic, yet largely evasive, domain of human behavior.

  16. Memory networks in tinnitus: a functional brain image study.

    Directory of Open Access Journals (Sweden)

    Maura Regina Laureano

    Full Text Available Tinnitus is characterized by the perception of sound in the absence of an external auditory stimulus. The network connectivity of auditory and non-auditory brain structures associated with emotion, memory and attention are functionally altered in debilitating tinnitus. Current studies suggest that tinnitus results from neuroplastic changes in the frontal and limbic temporal regions. The objective of this study was to use Single-Photon Emission Computed Tomography (SPECT to evaluate changes in the cerebral blood flow in tinnitus patients with normal hearing compared with healthy controls.Twenty tinnitus patients with normal hearing and 17 healthy controls, matched for sex, age and years of education, were subjected to Single Photon Emission Computed Tomography using the radiotracer ethylenedicysteine diethyl ester, labeled with Technetium 99 m (99 mTc-ECD SPECT. The severity of tinnitus was assessed using the "Tinnitus Handicap Inventory" (THI. The images were processed and analyzed using "Statistical Parametric Mapping" (SPM8.A significant increase in cerebral perfusion in the left parahippocampal gyrus (pFWE <0.05 was observed in patients with tinnitus compared with healthy controls. The average total THI score was 50.8+18.24, classified as moderate tinnitus.It was possible to identify significant changes in the limbic system of the brain perfusion in tinnitus patients with normal hearing, suggesting that central mechanisms, not specific to the auditory pathway, are involved in the pathophysiology of symptoms, even in the absence of clinically diagnosed peripheral changes.

  17. Poly(Lactic-co-Glycolic) Acid as a Carrier for Imaging Contrast Agents

    Science.gov (United States)

    Doiron, Amber L.; Homan, Kimberly A.; Emelianov, Stanislav; Brannon-Peppas, Lisa

    2010-01-01

    Purpose With the broadening field of nanomedicine poised for future molecular level therapeutics, nano-and microparticles intended for the augmentation of either single- or multimodal imaging are created with PLGA as the chief constituent and carrier. Methods Emulsion techniques were used to encapsulate hydrophilic and hydrophobic imaging contrast agents in PLGA particles. The imaging contrast properties of these PLGA particles were further enhanced by reducing silver onto the PLGA surface, creating a silver cage around the polymeric core. Results The MRI contrast agent Gd-DTPA and the exogenous dye rhodamine 6G were both encapsulated in PLGA and shown to enhance MR and fluorescence contrast, respectively. The silver nanocage built around PLGA nanoparticles exhibited strong near infrared light absorbance properties, making it a suitable contrast agent for optical imaging strategies such as photoacoustic imaging. Conclusions The biodegradable polymer PLGA is an extremely versatile nano- and micro-carrier for several imaging contrast agents with the possibility of targeting diseased states at a molecular level. PMID:19034628

  18. In vivo photothermal optical coherence tomography for non-invasive imaging of endogenous absorption agents.

    Science.gov (United States)

    Makita, Shuichi; Yasuno, Yoshiaki

    2015-05-01

    In vivo photothermal optical coherence tomography (OCT) is demonstrated for cross-sectional imaging of endogenous absorption agents. In order to compromise the sensitivity, imaging speed, and sample motion immunity, a new photothermal detection scheme and phase processing method are developed. Phase-resolved swept-source OCT and fiber-pigtailed laser diode (providing excitation at 406 nm) are combined to construct a high-sensitivity photothermal OCT system. OCT probe and excitation beam coaxially illuminate and are focused on tissues. The photothermal excitation and detection procedure is designed to obtain high efficiency of photothermal effect measurement. The principle and method of depth-resolved cross-sectional imaging of absorption agents with photothermal OCT has been derived. The phase-resolved thermal expansion detection algorithm without motion artifact enables in vivo detection of photothermal effect. Phantom imaging with a blood phantom and in vivo human skin imaging are conducted. A phantom with guinea-pig blood as absorber has been scanned by the photothermal OCT system to prove the concept of cross-sectional absorption agent imaging. An in vivo human skin measurement is also performed with endogenous absorption agents.

  19. Magnetic resonance imaging and cell-based neurorestorative therapy after brain injury

    Directory of Open Access Journals (Sweden)

    Quan Jiang

    2016-01-01

    Full Text Available Restorative cell-based therapies for experimental brain injury, such as stroke and traumatic brain injury, substantially improve functional outcome. We discuss and review state of the art magnetic resonance imaging methodologies and their applications related to cell-based treatment after brain injury. We focus on the potential of magnetic resonance imaging technique and its associated challenges to obtain useful new information related to cell migration, distribution, and quantitation, as well as vascular and neuronal remodeling in response to cell-based therapy after brain injury. The noninvasive nature of imaging might more readily help with translation of cell-based therapy from the laboratory to the clinic.

  20. Magnetic resonance imaging and cell-based neurorestorative therapy after brain injury

    Institute of Scientific and Technical Information of China (English)

    Quan Jiang

    2016-01-01

    Restorative cell-based therapies for experimental brain injury, such as stroke and traumatic brain injury, substantially improve functional outcome. We discuss and review state of the art magnetic resonance im-aging methodologies and their applications related to cell-based treatment after brain injury. We focus on the potential of magnetic resonance imaging technique and its associated challenges to obtain useful new information related to cell migration, distribution, and quantitation, as well as vascular and neuronal remodeling in response to cell-based therapy after brain injury. The noninvasive nature of imaging might more readily help with translation of cell-based therapy from the laboratory to the clinic.

  1. Diffusion Tensor Imaging: Application to the Study of the Developing Brain

    Science.gov (United States)

    Cascio, Carissa J.; Gerig, Guido; Piven, Joseph

    2007-01-01

    Objective: To provide an overview of diffusion tensor imaging (DTI) and its application to the study of white matter in the developing brain in both healthy and clinical samples. Method: The development of DTI and its application to brain imaging of white matter tracts is discussed. Forty-eight studies using DTI to examine diffusion properties of…

  2. Measurement of brain oxygenation changes using dynamic T1-weighted imaging

    DEFF Research Database (Denmark)

    Haddock, Bryan; Larsson, Henrik B W; Hansen, Adam E

    2013-01-01

    Magnetic resonance imaging (MRI) has proven useful in evaluating oxygenation in several types of tissue and blood. This study evaluates brain tissue oxygenation changes between normoxia and hyperoxia in healthy subjects using dynamic T1 and T2*-weighted imaging sequences. The change in FiO2 induced...... in the brain with a potential to provide quantitative information on tissue oxygenation....

  3. Seeing Is Believing: The Effect of Brain Images on Judgments of Scientific Reasoning

    Science.gov (United States)

    McCabe, David P.; Castel, Alan D.

    2008-01-01

    Brain images are believed to have a particularly persuasive influence on the public perception of research on cognition. Three experiments are reported showing that presenting brain images with articles summarizing cognitive neuroscience research resulted in higher ratings of scientific reasoning for arguments made in those articles, as compared…

  4. Brain and lung involvement of mycosis fungoides demonstrated by radionuclide imaging

    Energy Technology Data Exchange (ETDEWEB)

    Kim, E.E.; DeLand, F.H.; Maruyama, Y.

    1979-03-01

    A patient with advanced mycosis fungoides developed neurologic and respiratory symptoms and signs following multiple courses of chemotherapy and radiotherapy. Various repeated diagnostic procedures - including cranial computerized tomography and fiberoptic bronchoscopy with transbronchial lung biopsy - failed to demonstrate an unusual involvement of the brain and lungs by myocosis fungoides. Radionuclide brain imaging and gallium imaging of the lungs demonstrated diffuse lesions confirmed at autopsy.

  5. Value of C-11-methionine PET in imaging brain tumours and metastases

    NARCIS (Netherlands)

    Glaudemans, Andor W J M; Enting, Roeline; Heesters, Martinus; Dierckx, Rudi A J O; van Rheenen, Ronald W J; Walenkamp, Annemiek M E; Slart, Riemer H J A

    2013-01-01

    C-11-methionine (MET) is the most popular amino acid tracer used in PET imaging of brain tumours. Because of its characteristics, MET PET provides a high detection rate of brain tumours and good lesion delineation. This review focuses on the role of MET PET in imaging cerebral gliomas. The Introduct

  6. Image Data Mining for Pattern Classification and Visualization of Morphological Changes in Brain MR Images.

    Science.gov (United States)

    Murakawa, Saki; Ikuta, Rie; Uchiyama, Yoshikazu; Shiraishi, Junji

    2016-02-01

    Hospital information systems (HISs) and picture archiving and communication systems (PACSs) are archiving large amounts of data (i.e., "big data") that are not being used. Therefore, many research projects in progress are trying to use "big data" for the development of early diagnosis, prediction of disease onset, and personalized therapies. In this study, we propose a new method for image data mining to identify regularities and abnormalities in the large image data sets. We used 70 archived magnetic resonance (MR) images that were acquired using three-dimensional magnetization-prepared rapid acquisition with gradient echo (3D MP-RAGE). These images were obtained from the Alzheimer's disease neuroimaging initiative (ADNI) database. For anatomical standardization of the data, we used the statistical parametric mapping (SPM) software. Using a similarity matrix based on cross-correlation coefficients (CCs) calculated from an anatomical region and a hierarchical clustering technique, we classified all the abnormal cases into five groups. The Z score map identified the difference between a standard normal brain and each of those from the Alzheimer's groups. In addition, the scatter plot obtained from two similarity matrixes visualized the regularities and abnormalities in the image data sets. Image features identified using our method could be useful for understanding of image findings associated with Alzheimer's disease.

  7. Mechanistic and quantitative insight into cell surface targeted molecular imaging agent design.

    Science.gov (United States)

    Zhang, Liang; Bhatnagar, Sumit; Deschenes, Emily; Thurber, Greg M

    2016-05-05

    Molecular imaging agent design involves simultaneously optimizing multiple probe properties. While several desired characteristics are straightforward, including high affinity and low non-specific background signal, in practice there are quantitative trade-offs between these properties. These include plasma clearance, where fast clearance lowers background signal but can reduce target uptake, and binding, where high affinity compounds sometimes suffer from lower stability or increased non-specific interactions. Further complicating probe development, many of the optimal parameters vary depending on both target tissue and imaging agent properties, making empirical approaches or previous experience difficult to translate. Here, we focus on low molecular weight compounds targeting extracellular receptors, which have some of the highest contrast values for imaging agents. We use a mechanistic approach to provide a quantitative framework for weighing trade-offs between molecules. Our results show that specific target uptake is well-described by quantitative simulations for a variety of targeting agents, whereas non-specific background signal is more difficult to predict. Two in vitro experimental methods for estimating background signal in vivo are compared - non-specific cellular uptake and plasma protein binding. Together, these data provide a quantitative method to guide probe design and focus animal work for more cost-effective and time-efficient development of molecular imaging agents.

  8. Mechanistic and quantitative insight into cell surface targeted molecular imaging agent design

    Science.gov (United States)

    Zhang, Liang; Bhatnagar, Sumit; Deschenes, Emily; Thurber, Greg M.

    2016-05-01

    Molecular imaging agent design involves simultaneously optimizing multiple probe properties. While several desired characteristics are straightforward, including high affinity and low non-specific background signal, in practice there are quantitative trade-offs between these properties. These include plasma clearance, where fast clearance lowers background signal but can reduce target uptake, and binding, where high affinity compounds sometimes suffer from lower stability or increased non-specific interactions. Further complicating probe development, many of the optimal parameters vary depending on both target tissue and imaging agent properties, making empirical approaches or previous experience difficult to translate. Here, we focus on low molecular weight compounds targeting extracellular receptors, which have some of the highest contrast values for imaging agents. We use a mechanistic approach to provide a quantitative framework for weighing trade-offs between molecules. Our results show that specific target uptake is well-described by quantitative simulations for a variety of targeting agents, whereas non-specific background signal is more difficult to predict. Two in vitro experimental methods for estimating background signal in vivo are compared - non-specific cellular uptake and plasma protein binding. Together, these data provide a quantitative method to guide probe design and focus animal work for more cost-effective and time-efficient development of molecular imaging agents.

  9. Infectious diseases of the brain: imaging and differential diagnosis; Infektioese Hirnerkrankungen: Bildgebung und differenzialdiagnostische Aspekte

    Energy Technology Data Exchange (ETDEWEB)

    Haehnel, S.; Seitz, A. [Abt. Neuroradiologie, Neurologische Klinik, Universitaetsklinikum Heidelberg (Germany); Storch-Hagenlocher, B. [Abt. Neurologie, Neurologische Klinik, Universitaetsklinikum Heidelberg (Germany)

    2006-09-15

    Infectious diseases of the central nervous system have to be considered in differential diagnosis particularly in immunocompromised persons. Neuro-imaging, specifically advanced techniques such as diffusion weighted MRI and perfusion MRI contribute much to the differentiation of brain infections and for differentiating brain infections from other, for instance, neoplastic diseases. In this review we present the imaging criteria of the most important brains infections in adults and in pediatric patients and discuss differential diagnostic aspects in detail. (orig.)

  10. Pharmacology of radioiodinated hexadecenoic acid - a myocardial imaging agent

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Q.X.; Zhang, J.; Ji, Q.M.; Wang, Y.C.; Xie, D.F.; Hua, R.L.; He, W.Y.; Shi, X.C.; Li, Y.J.; Jiang, C.J.

    1984-04-01

    /sup 123/I- and /sup 131/I-labelled hexadecenoic acids (IHDA, radiochemical purity over 92%, dissolved in 6% bovine serum albumin solution) was investigated in vivo. ICR mice were administered IHDA via the tail vein. Maximum myocardial uptake (27.3 +- 5.1%) was reached about 0.5 min after the injection. The ratio of uptake in the heart to that in the lungs was 2.3, to that in liver 1.5 and to that in other organs 2.4 to 6.4. The dog myocardium was visualized distinctly within 3-5 min with a gamma camera after i.v. /sup 131/I-IHDA, and not interfered with by activities in the lungs, liver and other organs. The low blood levels at 20 min had little effect on the quality of the heart images.

  11. {sup 11}C-labeled stilbene derivatives as A{beta}-aggregate-specific PET imaging agents for Alzheimer's disease

    Energy Technology Data Exchange (ETDEWEB)

    Ono, Masahiro; Wilson, Alan; Nobrega, Jose; Westaway, David; Verhoeff, Paul; Zhuang Zhiping; Kung Meiping; Kung, Hank F. E-mail: kunghf@sunmac.spect.upenn.edu

    2003-08-01

    A series of stilbene derivatives as potential diagnostic imaging agents targeting amyloid plaques in Alzheimer's disease (AD) were synthesized and evaluated. The syntheses of the stilbenes were successfully achieved by a simple Wadsworth-Emmons reaction between diethyl (4-nitrobenzyl)phosphonate and 4-methoxybenzaldehyde. 4-N,N-dimethylamino-4'-methyoxy and the corresponding 4-N-monomethylamino-, 4'-hydroxy stilbenes showed good binding affinities towards A{beta} aggregates in vitro (K{sub i} < 10 nM). The {sup 11}C labeled 4-N-methylamino-4'-hydroxystilbene, [{sup 11}C]4, was prepared by {sup 11}C methylation of 4-amino-4'-hydroxystilbene. The [{sup 11}C]4 displayed a moderate lipophilicity (log P = 2.36), and showed a very good brain penetration and washout from normal rat brain after an iv injection. In vitro autoradiography of transgenic AD mouse brain sections showed a high specific labeling of {beta}-amyloid plaques, whereas the control sections showed no binding. Taken together the data suggest that a relatively simple stilbene derivative, [{sup 11}C]4, N-[{sup 11}C]methylamino-4'-hydroxystilbene, may be useful as a positron emission tomography (PET) imaging agent for mapping A{beta} plaques in the brain of patients with Alzheimer's disease.

  12. Brain MR imaging in children with psychomotor developmental delay

    Energy Technology Data Exchange (ETDEWEB)

    Hirai, Toshinori; Korogi, Yukunori; Sakamoto, Yuji; Furusawa, Mitsuhiro; Hamatake, Satoshi; Takahashi, Mutsumasa (Kumamoto Univ. (Japan). School of Medicine)

    1994-06-01

    Fifty-two patients with developmental delay of unknown cause underwent MR imaging of the brain. Their ages ranged from 5 months to 22 years, with a mean of 2.2 years. Thirty-seven (71%) had positive MR findings, including nine with congenital malformation, nine with atrophy, six with white matter lesion, five with delayed myelination, five with atrophy and delayed myelination, two with acquired injury of corpus callosum, and one with ulegyria. Congenital malformations obtained included holoprosencephaly, polymicrogyria, dysgenesis of corpus callosum, hypoplasia of cerebellum, and tuberous sclerosis. Abnormal MR findings were frequently observed both in the children with neurologic physical findings and in generally retarded children, while in the children with suspected autism, MR imaging did not demonstrate any abnormalities. Of 24 patients with epilepsy, abnormal MR findings were obtained in 17 patients (71%). The frequency of white matter lesion and atrophy was slightly higher in the patients with epilepsy. However, no significant correlations were found between MR findings and the presence of epilepsy. Also, no significant correlations were obtained between MR findings and the degree of developmental quotient (DQ). Severely injured cases did not necessarily show abnormal findings on MRI. (author).

  13. Magnetic resonance imaging of the brain in patients with migraine

    Energy Technology Data Exchange (ETDEWEB)

    Igarashi, H.; Sakai, F.; Kan, S.; Okada, J.; Tazaki, Y. (Kitasato Univ., Sagamihara, Kanagawa (Japan). School of Medicine)

    1991-05-01

    Magnetic resonance imaging (MRI) was studied in 91 patients with migraine and in 98 controls. Risk factors known to cause MRI lesions were carefully examined. In 36 patients with migraine (39.6%), small foci of high intensity on T{sub 2}-weighted and proton-density-weighted images were seen in the white matter. Of patients with migraine who were less than 40 years old and without any risk factor, 29.4% showed lesions on MRI; this was singificantly higher than the 11.2% for the group of age-matched controls (n=98). The lesions were distributed predominantly in the centrum semiovale and frontal white matter in young patients, but extended to the deeper white matter at the level of basal ganglia in the older age group. The side of the MRI lesions did not always correspond to the side of usual aura or headache. Migraine-related variables such as type of migraine, frequency, duration or intensity of headache or consumption of ergotamine showed no significant correlation with the incidence om MRI abnormalities. The data indicated that migraine may be associated with early pathologic changes in the brain. 26 refs., 4 figs., 3 tabs.

  14. A review of multivariate methods in brain imaging data fusion

    Science.gov (United States)

    Sui, Jing; Adali, Tülay; Li, Yi-Ou; Yang, Honghui; Calhoun, Vince D.

    2010-03-01

    On joint analysis of multi-task brain imaging data sets, a variety of multivariate methods have shown their strengths and been applied to achieve different purposes based on their respective assumptions. In this paper, we provide a comprehensive review on optimization assumptions of six data fusion models, including 1) four blind methods: joint independent component analysis (jICA), multimodal canonical correlation analysis (mCCA), CCA on blind source separation (sCCA) and partial least squares (PLS); 2) two semi-blind methods: parallel ICA and coefficient-constrained ICA (CC-ICA). We also propose a novel model for joint blind source separation (BSS) of two datasets using a combination of sCCA and jICA, i.e., 'CCA+ICA', which, compared with other joint BSS methods, can achieve higher decomposition accuracy as well as the correct automatic source link. Applications of the proposed model to real multitask fMRI data are compared to joint ICA and mCCA; CCA+ICA further shows its advantages in capturing both shared and distinct information, differentiating groups, and interpreting duration of illness in schizophrenia patients, hence promising applicability to a wide variety of medical imaging problems.

  15. Developing a multiscale, multi-resolution agent-based brain tumor model by graphics processing units

    Directory of Open Access Journals (Sweden)

    Zhang Le

    2011-12-01

    Full Text Available Abstract Multiscale agent-based modeling (MABM has been widely used to simulate Glioblastoma Multiforme (GBM and its progression. At the intracellular level, the MABM approach employs a system of ordinary differential equations to describe quantitatively specific intracellular molecular pathways that determine phenotypic switches among cells (e.g. from migration to proliferation and vice versa. At the intercellular level, MABM describes cell-cell interactions by a discrete module. At the tissue level, partial differential equations are employed to model the diffusion of chemoattractants, which are the input factors of the intracellular molecular pathway. Moreover, multiscale analysis makes it possible to explore the molecules that play important roles in determining the cellular phenotypic switches that in turn drive the whole GBM expansion. However, owing to limited computational resources, MABM is currently a theoretical biological model that uses relatively coarse grids to simulate a few cancer cells in a small slice of brain cancer tissue. In order to improve this theoretical model to simulate and predict actual GBM cancer progression in real time, a graphics processing unit (GPU-based parallel computing algorithm was developed and combined with the multi-resolution design to speed up the MABM. The simulated results demonstrated that the GPU-based, multi-resolution and multiscale approach can accelerate the previous MABM around 30-fold with relatively fine grids in a large extracellular matrix. Therefore, the new model has great potential for simulating and predicting real-time GBM progression, if real experimental data are incorporated.

  16. Effect of Harderian adenectomy on the statistical analyses of mouse brain imaging using positron emission tomography.

    Science.gov (United States)

    Kim, Minsoo; Woo, Sang-Keun; Yu, Jung Woo; Lee, Yong Jin; Kim, Kyeong Min; Kang, Joo Hyun; Eom, Kidong; Nahm, Sang-Soep

    2014-01-01

    Positron emission tomography (PET) using 2-deoxy-2-[(18)F] fluoro-D-glucose (FDG) as a radioactive tracer is a useful technique for in vivo brain imaging. However, the anatomical and physiological features of the Harderian gland limit the use of FDG-PET imaging in the mouse brain. The gland shows strong FDG uptake, which in turn results in distorted PET images of the frontal brain region. The purpose of this study was to determine if a simple surgical procedure to remove the Harderian gland prior to PET imaging of mouse brains could reduce or eliminate FDG uptake. Measurement of FDG uptake in unilaterally adenectomized mice showed that the radioactive signal emitted from the intact Harderian gland distorts frontal brain region images. Spatial parametric measurement analysis demonstrated that the presence of the Harderian gland could prevent accurate assessment of brain PET imaging. Bilateral Harderian adenectomy efficiently eliminated unwanted radioactive signal spillover into the frontal brain region beginning on postoperative Day 10. Harderian adenectomy did not cause any post-operative complications during the experimental period. These findings demonstrate the benefits of performing a Harderian adenectomy prior to PET imaging of mouse brains.

  17. Nanoparticles in magnetic resonance imaging: from simple to dual contrast agents

    Science.gov (United States)

    Estelrich, Joan; Sánchez-Martín, María Jesús; Busquets, Maria Antònia

    2015-01-01

    Magnetic resonance imaging (MRI) has become one of the most widely used and powerful tools for noninvasive clinical diagnosis owing to its high degree of soft tissue contrast, spatial resolution, and depth of penetration. MRI signal intensity is related to the relaxation times (T1, spin–lattice relaxation and T2, spin–spin relaxation) of in vivo water protons. To increase contrast, various inorganic nanoparticles and complexes (the so-called contrast agents) are administered prior to the scanning. Shortening T1 and T2 increases the corresponding relaxation rates, 1/T1 and 1/T2, producing hyperintense and hypointense signals respectively in shorter times. Moreover, the signal-to-noise ratio can be improved with the acquisition of a large number of measurements. The contrast agents used are generally based on either iron oxide nanoparticles or ferrites, providing negative contrast in T2-weighted images; or complexes of lanthanide metals (mostly containing gadolinium ions), providing positive contrast in T1-weighted images. Recently, lanthanide complexes have been immobilized in nanostructured materials in order to develop a new class of contrast agents with functions including blood-pool and organ (or tumor) targeting. Meanwhile, to overcome the limitations of individual imaging modalities, multimodal imaging techniques have been developed. An important challenge is to design all-in-one contrast agents that can be detected by multimodal techniques. Magnetoliposomes are efficient multimodal contrast agents. They can simultaneously bear both kinds of contrast and can, furthermore, incorporate targeting ligands and chains of polyethylene glycol to enhance the accumulation of nanoparticles at the site of interest and the bioavailability, respectively. Here, we review the most important characteristics of the nanoparticles or complexes used as MRI contrast agents. PMID:25834422

  18. Deep-brain imaging via epi-fluorescence Computational Cannula Microscopy

    Science.gov (United States)

    Kim, Ganghun; Nagarajan, Naveen; Pastuzyn, Elissa; Jenks, Kyle; Capecchi, Mario; Shepherd, Jason; Menon, Rajesh

    2017-03-01

    Here we demonstrate widefield (field diameter = 200 μm) fluorescence microscopy and video imaging inside the rodent brain at a depth of 2 mm using a simple surgical glass needle (cannula) of diameter 0.22 mm as the primary optical element. The cannula guides excitation light into the brain and the fluorescence signal out of the brain. Concomitant image-processing algorithms are utilized to convert the spatially scrambled images into fluorescent images and video. The small size of the cannula enables minimally invasive imaging, while the long length (>2 mm) allow for deep-brain imaging with no additional complexity in the optical system. Since no scanning is involved, widefield fluorescence video at the native frame rate of the camera can be achieved.

  19. Deep-brain imaging via epi-fluorescence Computational Cannula Microscopy

    Science.gov (United States)

    Kim, Ganghun; Nagarajan, Naveen; Pastuzyn, Elissa; Jenks, Kyle; Capecchi, Mario; Shepherd, Jason; Menon, Rajesh

    2017-01-01

    Here we demonstrate widefield (field diameter = 200 μm) fluorescence microscopy and video imaging inside the rodent brain at a depth of 2 mm using a simple surgical glass needle (cannula) of diameter 0.22 mm as the primary optical element. The cannula guides excitation light into the brain and the fluorescence signal out of the brain. Concomitant image-processing algorithms are utilized to convert the spatially scrambled images into fluorescent images and video. The small size of the cannula enables minimally invasive imaging, while the long length (>2 mm) allow for deep-brain imaging with no additional complexity in the optical system. Since no scanning is involved, widefield fluorescence video at the native frame rate of the camera can be achieved. PMID:28317915

  20. Water-soluble L-cysteine-coated FePt nanoparticles as dual MRI/CT imaging contrast agent for glioma.

    Science.gov (United States)

    Liang, Shuyan; Zhou, Qing; Wang, Min; Zhu, Yanhong; Wu, Qingzhi; Yang, Xiangliang

    2015-01-01

    Nanoparticles (NPs) are advantageous for the delivery of diagnosis agents to brain tumors. In this study, we attempted to develop an L-cysteine coated FePt (FePt-Cys) NP as MRI/CT imaging contrast agent for the diagnosis of malignant gliomas. FePt-Cys NPs were synthesized through a co-reduction route, which was characterized by transmission electron microscopy, high-resolution transmission electron microscopy, powder X-ray diffraction, Fourier transform infrared spectroscopy, and dynamic light scattering. The MRI and CT imaging ability of FePt-Cys NPs was evaluated using different gliomas cells (C6, SGH44, U251) as the model. Furthermore, the biocompatibility of the as-synthesized FePt-Cys NPs was evaluated using three different cell lines (ECV304, L929, and HEK293) as the model. The results showed that FePt-Cys NPs displayed excellent biocompatibility and good MRI/CT imaging ability, thereby indicating promising potential as a dual MRI/CT contrast agent for the diagnosis of brain malignant gliomas.

  1. Real-time imaging and quantification of brain delivery of liposomes.

    Science.gov (United States)

    Krauze, Michal T; Forsayeth, John; Park, John W; Bankiewicz, Krystof S

    2006-11-01

    The surgical delivery of therapeutic agents into the parenchyma of the brain is problematic because it has been virtually impossible to know with any certainty where infused material is going, and how much to infuse. We have started to use liposomes loaded with Gadoteridol (GDL) as a tracer that allows us to follow infusions in real-time on magnetic resonance imaging (MRI). MRI allows precise tracking and measurement of liposomes loaded with markers and therapeutics. This review provides an overview of real-time delivery of liposomes to the central nervous system (CNS), and discusses the technical aspects of delivery, liposomes as colloidal systems of delivery, real-time distribution of liposomes in CNS, and quantification of liposome distribution. Our data suggests that real-time monitoring of liposomal drug infusion is likely to improve outcomes of clinical trials where convection-enhanced delivery (CED) is being used to target drugs to specific brain structures through limitation of systemic toxicity and reduction of side effects. This review is a summary of work done by our group over the past four years.

  2. Level set method with automatic selective local statistics for brain tumor segmentation in MR images.

    Science.gov (United States)

    Thapaliya, Kiran; Pyun, Jae-Young; Park, Chun-Su; Kwon, Goo-Rak

    2013-01-01

    The level set approach is a powerful tool for segmenting images. This paper proposes a method for segmenting brain tumor images from MR images. A new signed pressure function (SPF) that can efficiently stop the contours at weak or blurred edges is introduced. The local statistics of the different objects present in the MR images were calculated. Using local statistics, the tumor objects were identified among different objects. In this level set method, the calculation of the parameters is a challenging task. The calculations of different parameters for different types of images were automatic. The basic thresholding value was updated and adjusted automatically for different MR images. This thresholding value was used to calculate the different parameters in the proposed algorithm. The proposed algorithm was tested on the magnetic resonance images of the brain for tumor segmentation and its performance was evaluated visually and quantitatively. Numerical experiments on some brain tumor images highlighted the efficiency and robustness of this method.

  3. An Improved Image Mining Technique For Brain Tumour Classification Using Efficient Classifier

    Directory of Open Access Journals (Sweden)

    P. Rajendran

    2009-12-01

    Full Text Available An improved image mining technique for brain tumor classification using pruned association rule with MARI algorithm is presented in this paper. The method proposed makes use of association rule mining technique to classify the CT scan brain images into three categories namely normal, benign and malign. It combines the low-level features extracted from images and high level knowledge from specialists. The developed algorithm can assist the physicians for efficient classification with multiple keywords per image to improve the accuracy. The experimental result on pre-diagnosed database of brain images showed 96% and 93% sensitivity and accuracy respectively.Keywords- Data mining; Image ming; Association rule mining; Medical Imaging; Medical image diagnosis; Classification;

  4. Palladium nanosheets as highly stable and effective contrast agents for in vivo photoacoustic molecular imaging

    Science.gov (United States)

    Nie, Liming; Chen, Mei; Sun, Xiaolian; Rong, Pengfei; Zheng, Nanfeng; Chen, Xiaoyuan

    2014-01-01

    A stable and efficient contrast agent is highly desirable for photoacoustic (PA) imaging applications. Recently gold nanostructures have been widely reported and studied for PA imaging and photothermal therapy. However, the structures of the nonspherical gold nanoparticles are easily destroyed after laser irradiation and thus may fail to complete the intended tasks. In this study, we propose to apply palladium nanosheets (PNSs), with strong optical absorption in the near-infrared (NIR) region, as a new class of exogenous PA contrast agents. PA and ultrasound (US) images were acquired sequentially by a portable and fast photoacoustic tomography (PAT) system with a hand-held transducer. Significant and long-lasting imaging enhancement in SCC7 head and neck squamous cell carcinoma was successfully observed in mice by PAT over time after tail vein administration of PNSs. The morphology and functional perfusion of the tumors were delineated in PA images due to the nanoparticle accumulation. PAT of the main organs was also conducted ex vivo to trace the fate of PNSs, which was further validated by inductively coupled plasma atomic emission spectrometry (ICP-AES). No obvious toxic effect was observed by in vitro MTT assay and ex vivo histological examination 7 days after PNS administration. With the combination of a portable imaging instrument and signal specificity, PNSs might be applied as stable and effective agents for photoacoustic cancer detection, diagnosis and treatment guidance.

  5. Family of enhanced photoacoustic imaging agents for high-sensitivity and multiplexing studies in living mice.

    Science.gov (United States)

    de la Zerda, Adam; Bodapati, Sunil; Teed, Robert; May, Salomón Y; Tabakman, Scott M; Liu, Zhuang; Khuri-Yakub, Butrus T; Chen, Xiaoyuan; Dai, Hongjie; Gambhir, Sanjiv S

    2012-06-26

    Photoacoustic imaging is a unique modality that overcomes to a great extent the resolution and depth limitations of optical imaging while maintaining relatively high contrast. However, since many diseases will not manifest an endogenous photoacoustic contrast, it is essential to develop exogenous photoacoustic contrast agents that can target diseased tissue(s). Here we present a family of novel photoacoustic contrast agents that are based on the binding of small optical dyes to single-walled carbon nanotubes (SWNT-dye). We synthesized five different SWNT-dye contrast agents using different optical dyes, creating five "flavors" of SWNT-dye nanoparticles. In particular, SWNTs that were coated with either QSY(21) (SWNT-QSY) or indocyanine green (SWNT-ICG) exhibited over 100-times higher photoacoustic contrast in living animals compared to plain SWNTs, leading to subnanomolar sensitivities. We then conjugated the SWNT-dye conjugates with cyclic Arg-Gly-Asp peptides to molecularly target the α(v)β(3) integrin, which is associated with tumor angiogenesis. Intravenous administration of these tumor-targeted imaging agents to tumor-bearing mice showed significantly higher photoacoustic signal in the tumor than in mice injected with the untargeted contrast agent. Finally, we were able to spectrally separate the photoacoustic signals of SWNT-QSY and SWNT-ICG in living animals injected subcutaneously with both particles in the same location, opening the possibility for multiplexing in vivo studies.

  6. Cluster imaging of multi-brain networks (CIMBN: a general framework for hyperscanning and modeling a group of interacting brains

    Directory of Open Access Journals (Sweden)

    Lian eDuan

    2015-07-01

    Full Text Available Studying the neural basis of human social interactions is a key topic in the field of social neuroscience. Brain imaging studies in this field usually focus on the neural correlates of the social interactions between two participants. However, as the participant number further increases, even by a small amount, great difficulties raise. One challenge is how to concurrently scan all the interacting brains with high ecological validity, especially for a large number of participants. The other challenge is how to effectively model the complex group interaction behaviors emerging from the intricate neural information exchange among a group of socially organized people. Confronting these challenges, we propose a new approach called Cluster Imaging of Multi-brain Networks (CIMBN. CIMBN consists of two parts. The first part is a cluster imaging technique with high ecological validity based on multiple functional near-infrared spectroscopy (fNIRS systems. Using this technique, we can easily extend the simultaneous imaging capacity of social neuroscience studies up to dozens of participants. The second part of CIMBN is a multi-brain network (MBN modeling method based on graph theory. By taking each brain as a network node and the relationship between any two brains as a network edge, one can construct a network model for a group of interacting brains. The emergent group social behaviors can then be studied using the network’s properties, such as its topological structure and information exchange efficiency. Although there is still much work to do, as a general framework for hyperscanning and modeling a group of interacting brains, CIMBN can provide new insights into the neural correlates of group social interactions, and advance social neuroscience and social psychology.

  7. Development of a high angular resolution diffusion imaging human brain template.

    Science.gov (United States)

    Varentsova, Anna; Zhang, Shengwei; Arfanakis, Konstantinos

    2014-05-01

    Brain diffusion templates contain rich information about the microstructure of the brain, and are used as references in spatial normalization or in the development of brain atlases. The accuracy of diffusion templates constructed based on the diffusion tensor (DT) model is limited in regions with complex neuronal micro-architecture. High angular resolution diffusion imaging (HARDI) overcomes limitations of the DT model and is capable of resolving intravoxel heterogeneity. However, when HARDI is combined with multiple-shot sequences to minimize image artifacts, the scan time becomes inappropriate for human brain imaging. In this work, an artifact-free HARDI template of the human brain was developed from low angular resolution multiple-shot diffusion data. The resulting HARDI template was produced in ICBM-152 space based on Turboprop diffusion data, was shown to resolve complex neuronal micro-architecture in regions with intravoxel heterogeneity, and contained fiber orientation information consistent with known human brain anatomy.

  8. An Improved Image Mining Technique For Brain Tumour Classification Using Efficient Classifier

    OpenAIRE

    Rajendran, P.; M.Madheswaran

    2010-01-01

    An improved image mining technique for brain tumor classification using pruned association rule with MARI algorithm is presented in this paper. The method proposed makes use of association rule mining technique to classify the CT scan brain images into three categories namely normal, benign and malign. It combines the low-level features extracted from images and high level knowledge from specialists. The developed algorithm can assist the physicians for efficient classification with multiple ...

  9. Novel Tc-99m radiotracers for brain imaging

    Directory of Open Access Journals (Sweden)

    Alessandra Boschi

    2007-09-01

    Full Text Available A novel class of Tc-99m complexes able to cross the blood brain barrier has been investigated and described here. These compounds are formed by reacting the bis-substituted nitrido precusors [99mTc(N(PS2] (PS = phosphino-thiol ligand with triethylborane (BEt3 under strictly anhydrous conditions and using non-aqueous solvents. The molecular structure of these tracers was not fully established, but preliminary experimental evidence suggests that they result from the interaction of the Lewis base [99mTc(N(PS2] with the Lewis acid BEt3, which leads to the formation of the novel -B-Nº Tc- adduct. After purification and recovery in a physiological solution, the new borane-nitrido Tc-99m derivatives were injected in rats for evaluating their in vivo biological behavior. Results showed a significant accumulation in brain tissue, thus indicating that these complexes are capable of penetrating the intact blood brain barrier. Uptake in the central nervous system was confirmed by imaging the distribution of activity on the integrated living animal using a YAP(SSPECT small animal scanner.Uma nova classe de complexos de Tc-99m capazes de atravessar a barreira hemato-encefálica foi investigada e descrita neste trabalho. Estes compostos são formados reagindo os precursores bissubstituídos do nitrido [99mTc(N(PS2] (PS = phosphino-tiol ligante com trietillborano (BEt3 sob restritas condições anidras e usando solventes não aquosos. A estrutura molecular desses traçadores não foi totalmente estabelecida, mas evidências experimentais preliminares sugerem que eles resultam da interação da base de Lewis [99mTc(N(PS2] com o ácido de Lewis BEt3, levando a formação do novo aducto -B-Nº Tc-. Após purificação e recuperação em uma solução fisiológica, os novos derivados borano-nitrido-Tc-99m foram injetados em ratos para avaliação de seu comportamento biológico in vivo. Os resultados mostraram uma acumulação significativa no tecido cerebral

  10. High-resolution in vivo Wistar rodent brain atlas based on T1 weighted image

    Science.gov (United States)

    Huang, Su; Lu, Zhongkang; Huang, Weimin; Seramani, Sankar; Ramasamy, Boominathan; Sekar, Sakthivel; Guan, Cuntai; Bhakoo, Kishore

    2016-03-01

    Image based atlases for rats brain have a significant impact on pre-clinical research. In this project we acquired T1-weighted images from Wistar rodent brains with fine 59μm isotropical resolution for generation of the atlas template image. By applying post-process procedures using a semi-automatic brain extraction method, we delineated the brain tissues from source data. Furthermore, we applied a symmetric group-wise normalization method to generate an optimized template of T1 image of rodent brain, then aligned our template to the Waxholm Space. In addition, we defined several simple and explicit landmarks to corresponding our template with the well known Paxinos stereotaxic reference system. Anchoring at the origin of the Waxholm Space, we applied piece-wise linear transformation method to map the voxels of the template into the coordinates system in Paxinos' stereotoxic coordinates to facilitate the labelling task. We also cross-referenced our data with both published rodent brain atlas and image atlases available online, methodologically labelling the template to produce a Wistar brain atlas identifying more than 130 structures. Particular attention was paid to the cortex and cerebellum, as these areas encompass the most researched aspects of brain functions. Moreover, we adopted the structure hierarchy and naming nomenclature common to various atlases, so that the names and hierarchy structure presented in the atlas are readily recognised for easy use. It is believed the atlas will present a useful tool in rodent brain functional and pharmaceutical studies.

  11. Long-Lasting and Efficient Tumor Imaging Using a High Relaxivity Polysaccharide Nanogel Magnetic Resonance Imaging Contrast Agent.

    Science.gov (United States)

    Chan, Minnie; Lux, Jacques; Nishimura, Tomoki; Akiyoshi, Kazunari; Almutairi, Adah

    2015-09-14

    Clinically approved small-molecule magnetic resonance imaging (MRI) contrast agents are all rapidly cleared from the body and offer weak signal enhancement. To avoid repeated administration of contrast agent and improve signal-to-noise ratios, agents with stronger signal enhancement and better retention in tumors are needed. Therefore, we focused on hydrogels because of their excellent water accessibility and biodegradability. Gadolinium (Gd)-chelating cross-linkers were incorporated into self-assembled pullulan nanogels to both impart magnetic properties and to stabilize this material that has been extensively studied for medical applications. We show that these Gd-chelating pullulan nanogels (Gd-CHPOA) have the highest reported relaxivity for any hydrogel-based particles and accumulate in the 4T1 tumors in mice at high levels 4 h after injection. This combination offers high signal enhancement and lasts up to 7 days to delineate the tumor clearly for longer imaging time scales. Importantly, this long-term accumulation does not cause any damage or toxicity in major organs up to three months after injection. Our work highlights the clinical potential of Gd-CHPOA as a tumor-imaging MRI contrast agent, permitting tumor identification and assessment with a high signal-to-background ratio.

  12. A peptide for targeted, systemic delivery of imaging and therapeutic compounds into acute brain injuries

    Science.gov (United States)

    Mann, Aman P.; Scodeller, Pablo; Hussain, Sazid; Joo, Jinmyoung; Kwon, Ester; Braun, Gary B.; Mölder, Tarmo; She, Zhi-Gang; Kotamraju, Venkata Ramana; Ranscht, Barbara; Krajewski, Stan; Teesalu, Tambet; Bhatia, Sangeeta; Sailor, Michael J.; Ruoslahti, Erkki

    2016-01-01

    Traumatic brain injury (TBI) is a major health and socio-economic problem, but no pharmacological agent is currently approved for the treatment of acute TBI. Thus, there is a great need for advances in this field. Here, we describe a short peptide (sequence CAQK) identified by in vivo phage display screening in mice with acute brain injury. The CAQK peptide selectively binds to injured mouse and human brain, and systemically injected CAQK specifically homes to sites of brain injury in mouse models. The CAQK target is a proteoglycan complex upregulated in brain injuries. Coupling to CAQK increased injury site accumulation of systemically administered molecules ranging from a drug-sized molecule to nanoparticles. CAQK-coated nanoparticles containing silencing oligonucleotides provided the first evidence of gene silencing in injured brain parenchyma by systemically administered siRNA. These findings present an effective targeting strategy for the delivery of therapeutics in clinical management of acute brain injuries. PMID:27351915

  13. A peptide for targeted, systemic delivery of imaging and therapeutic compounds into acute brain injuries

    Science.gov (United States)

    Mann, Aman P.; Scodeller, Pablo; Hussain, Sazid; Joo, Jinmyoung; Kwon, Ester; Braun, Gary B.; Mölder, Tarmo; She, Zhi-Gang; Kotamraju, Venkata Ramana; Ranscht, Barbara; Krajewski, Stan; Teesalu, Tambet; Bhatia, Sangeeta; Sailor, Michael J.; Ruoslahti, Erkki

    2016-06-01

    Traumatic brain injury (TBI) is a major health and socio-economic problem, but no pharmacological agent is currently approved for the treatment of acute TBI. Thus, there is a great need for advances in this field. Here, we describe a short peptide (sequence CAQK) identified by in vivo phage display screening in mice with acute brain injury. The CAQK peptide selectively binds to injured mouse and human brain, and systemically injected CAQK specifically homes to sites of brain injury in mouse models. The CAQK target is a proteoglycan complex upregulated in brain injuries. Coupling to CAQK increased injury site accumulation of systemically administered molecules ranging from a drug-sized molecule to nanoparticles. CAQK-coated nanoparticles containing silencing oligonucleotides provided the first evidence of gene silencing in injured brain parenchyma by systemically administered siRNA. These findings present an effective targeting strategy for the delivery of therapeutics in clinical management of acute brain injuries.

  14. Imaging plasma docosahexaenoic acid (dha incorporation into the brain in vivo, as a biomarker of brain DHA: Metabolism and neurotransmission

    Directory of Open Access Journals (Sweden)

    Rapoport Stanley I.

    2011-09-01

    Full Text Available Docosahexaenoic acid (DHA is critical for normal brain structure and function, and its brain concentration depends on dietary DHA content and hepatic conversion from its dietary derived n-3 precursor, a-linolenic acid (α-LNA. We developed an in vivo method in rats using quantitative autoradiography to image incorporation into brain of unesterified plasma DHA, and showed that the incorporation rate equals the rate of brain metabolic DHA consumption. Thus, quantitative imaging of DHA incorporation from plasma into brain can be used as a biomarker of brain DHA metabolism and neurotransmission. The method has been extended to humans with the use of positron emission tomography (PET. Furthermore, imaging in unanesthetized rats using DHA incorporation as a biomarker in response to N-methyl-D-aspartate (NMDA administration confirms that regional DHA signaling is independent of extracellular calcium, and likely mediated by a calcium-independent phospholipase A2 (iPLA2. Studies in mice in which iPLA2-VIA (β was knocked out confirmed that this enzyme is critical for baseline and muscarinic cholinergic signaling involving DHA.

  15. RGD-based strategies for selective delivery of therapeutics and imaging agents to the tumour vasculature

    NARCIS (Netherlands)

    Temming, K; Molema, G; Kok, RJ

    2005-01-01

    During the past decade, RGD-peptides have become a popular tool for the targeting of drugs and imaging agents to a(v)beta(3)-integrin expressing tumour vasculature. RGD-peptides have been introduced by recombinant means into therapeutic proteins and viruses. Chemical means have been applied to coupl

  16. Injury and repair in perinatal brain injury: Insights from non-invasive MR perfusion imaging.

    Science.gov (United States)

    Wintermark, Pia

    2015-03-01

    Injury to the developing brain remains an important complication in critically ill newborns, placing them at risk for future neurodevelopment impairments. Abnormal brain perfusion is often a key mechanism underlying neonatal brain injury. A better understanding of how alternations in brain perfusion can affect normal brain development will permit the development of therapeutic strategies that prevent and/or minimize brain injury and improve the neurodevelopmental outcome of these high-risk newborns. Recently, non-invasive MR perfusion imaging of the brain has been successfully applied to the neonatal brain, which is known to be smaller and have lower brain perfusion compared to older children and adults. This article will present an overview of the potential role of non-invasive perfusion imaging by MRI to study maturation, injury, and repair in perinatal brain injury and demonstrate why this perfusion sequence is an important addition to current neonatal imaging protocols, which already include different sequences to assess the anatomy and metabolism of the neonatal brain.

  17. Utility of susceptibility-weighted imaging and arterial spin perfusion imaging in pediatric brain arteriovenous shunting

    Energy Technology Data Exchange (ETDEWEB)

    Nabavizadeh, Seyed Ali; Edgar, J.C.; Vossough, Arastoo [University of Pennsylvania, Department of Radiology, Philadelphia, PA (United States); Children' s Hospital of Philadelphia, Department of Radiology, Philadelphia, PA (United States)

    2014-10-15

    The objectives of the study are to investigate the application of susceptibility-weighted imaging (SWI) and arterial spin labeling (ASL) imaging in the assessment of shunting and the draining veins in pediatric patients with arteriovenous shunting and compare the utility of SWI and ASL with conventional MR and digital subtraction angiography (DSA). This study is a retrospective study of 19 pediatric patients with arteriovenous shunting on brain MRI who were also evaluated with DSA. We assessed the ability of conventional MRI sequences, susceptibility magnitude images, phase-filtered SWI images, and pulsed ASL images in the detection of arteriovenous (AV) shunting, number of draining veins and drainage pathways in comparison to DSA. The mean number of detected draining veins on DSA (3.63) was significantly higher compared to SWI phase-filtered image (mean = 2.72), susceptibility magnitude image (mean = 2.92), ASL (mean = 1.76) and conventional MRI (2.47) (p < 0.05). Pairwise comparison of DSA difference scores (i.e., difference between MR modalities in the number of missed draining veins) revealed no difference between the MR modalities (p > 0.05). ASL was the only method that correctly identified superficial and deep venous drainage in all patients. Regarding detection of shunting, ASL, SWI phase-filtered, and magnitude images demonstrated shunting in 100, 83, and 84 % of patients, respectively. SWI depicts a higher number of draining vein compared to conventional MR pulse sequences. ASL is a sensitive approach in showing 100 % sensitivity in the detection of AV shunting and in the diagnosis of the pattern of venous drainage. The present findings suggest the added utility of both SWI and ASL in the assessment of AV shunting. (orig.)

  18. Label-free live brain imaging and targeted patching with third-harmonic generation microscopy

    Science.gov (United States)

    Witte, Stefan; Negrean, Adrian; Lodder, Johannes C.; de Kock, Christiaan P. J.; Testa Silva, Guilherme; Mansvelder, Huibert D.; Louise Groot, Marie

    2011-01-01

    The ability to visualize neurons inside living brain tissue is a fundamental requirement in neuroscience and neurosurgery. Especially the development of a noninvasive probe of brain morphology with micrometer-scale resolution is highly desirable, as it would provide a noninvasive approach to optical biopsies in diagnostic medicine. Two-photon laser-scanning microscopy (2PLSM) is a powerful tool in this regard, and has become the standard for minimally invasive high-resolution imaging of living biological samples. However, while 2PLSM-based optical methods provide sufficient resolution, they have been hampered by the requirement for fluorescent dyes to provide image contrast. Here we demonstrate high-contrast imaging of live brain tissue at cellular resolution, without the need for fluorescent probes, using optical third-harmonic generation (THG). We exploit the specific geometry and lipid content of brain tissue at the cellular level to achieve partial phase matching of THG, providing an alternative contrast mechanism to fluorescence. We find that THG brain imaging allows rapid, noninvasive label-free imaging of neurons, white-matter structures, and blood vessels simultaneously. Furthermore, we exploit THG-based imaging to guide micropipettes towards designated neurons inside live tissue. This work is a major step towards label-free microscopic live brain imaging, and opens up possibilities for the development of laser-guided microsurgery techniques in the living brain. PMID:21444784

  19. New dual mode gadolinium nanoparticle contrast agent for magnetic resonance imaging.

    Directory of Open Access Journals (Sweden)

    Ketan B Ghaghada

    Full Text Available BACKGROUND: Liposomal-based gadolinium (Gd nanoparticles have elicited significant interest for use as blood pool and molecular magnetic resonance imaging (MRI contrast agents. Previous generations of liposomal MR agents contained gadolinium-chelates either within the interior of liposomes (core-encapsulated gadolinium liposomes or presented on the surface of liposomes (surface-conjugated gadolinium liposomes. We hypothesized that a liposomal agent that contained both core-encapsulated gadolinium and surface-conjugated gadolinium, defined herein as dual-mode gadolinium (Dual-Gd liposomes, would result in a significant improvement in nanoparticle-based T1 relaxivity over the previous generations of liposomal agents. In this study, we have developed and tested, both in vitro and in vivo, such a dual-mode liposomal-based gadolinium contrast agent. METHODOLOGY/PRINCIPAL FINDINGS: THREE TYPES OF LIPOSOMAL AGENTS WERE FABRICATED: core-encapsulated, surface-conjugated and dual-mode gadolinium liposomes. In vitro physico-chemical characterizations of the agents were performed to determine particle size and elemental composition. Gadolinium-based and nanoparticle-based T1 relaxivities of various agents were determined in bovine plasma. Subsequently, the agents were tested in vivo for contrast-enhanced magnetic resonance angiography (CE-MRA studies. Characterization of the agents demonstrated the highest gadolinium atoms per nanoparticle for Dual-Gd liposomes. In vitro, surface-conjugated gadolinium liposomes demonstrated the highest T1 relaxivity on a gadolinium-basis. However, Dual-Gd liposomes demonstrated the highest T1 relaxivity on a nanoparticle-basis. In vivo, Dual-Gd liposomes resulted in the highest signal-to-noise ratio (SNR and contrast-to-noise ratio in CE-MRA studies. CONCLUSIONS/SIGNIFICANCE: The dual-mode gadolinium liposomal contrast agent demonstrated higher particle-based T1 relaxivity, both in vitro and in vivo, compared to either the

  20. Gadolinium contrast agent selection and optimal use for body MR imaging.

    Science.gov (United States)

    Guglielmo, Flavius F; Mitchell, Donald G; Gupta, Shiva

    2014-07-01

    Proper selection of a gadolinium-based contrast agent (GBCA) for body magnetic resonance imaging (MRI) cases requires understanding the indication for the MRI exam, the key features of the different GBCAs, and the effect that the GBCA has on the selected imaging protocol. The different categories of GBCAs require timing optimization on postcontrast sequences and adjusting imaging parameters to obtain the highest T1 contrast. Gadoxetate disodium has many advantages when evaluating liver lesions, although there are caveats and limitations that need to be understood. Gadobenate dimeglumine, a high-relaxivity GBCA, can be used for indications when stronger T1 relaxivity is needed.

  1. Brain natriuretic peptide in pulmonary arterial hypertension: biomarker and potential therapeutic agent

    Directory of Open Access Journals (Sweden)

    Brian Casserly

    2009-11-01

    Full Text Available Brian Casserly, James R KlingerDivision of Pulmonary and Critical Care Medicine, The Memorial Hospital of Rhode Island, Pawtucket, RI, Rhode Island Hospital, Providence, RI, Alpert Medical School of Brown University, Providence, RI, USAAbstract: B-type natriuretic peptide (BNP is a member of the natriuretic peptide family, a group of widely distributed, but evolutionarily conserved, polypeptide mediators that exert myriad cardiovascular effects. BNP is a potent vasodilator with mitogenic, hypertrophic and pro-inflammatory properties that is upregulated in pulmonary hypertensive diseases. Circulating levels of BNP correlate with mean pulmonary arterial pressure (mPAP and pulmonary vascular resistance (PVR in patients with pulmonary arterial hypertension (PAH. Elevated plasma BNP levels are associated with increased mortality in patients with PAH and a fall in BNP levels after therapy is associated with improved survival. These findings have important clinical implications in that a noninvasive blood test may be used to identify PAH patients at high-risk of decompensation and to guide pulmonary vasodilator therapy. BNP also has several biologic effects that could be beneficial to patients with PAH. However, lack of a convenient method for achieving sustained increases in circulating BNP levels has impeded the development of BNP as a therapy for treating pulmonary hypertension. New technologies that allow transdermal or oral administration of the natriuretic peptides have the potential to greatly accelerate research into therapeutic use of BNP for cor pulmonale and pulmonary vascular diseases. This review will examine the basic science and clinical research that has led to our understanding of the role of BNP in cardiovascular physiology, its use as a biomarker of right ventricular function and its therapeutic potential for managing patients with pulmonary vascular disease.Keywords: brain natriuretic peptide, pulmonary artery hypertension

  2. Detection of Brain Tumor and Extraction of Texture Features using Magnetic Resonance Images

    Directory of Open Access Journals (Sweden)

    Prof. Dilip Kumar Gandhi

    2012-10-01

    Full Text Available Brain Cancer Detection system is designed. Aim of this paper is to locate the tumor and determine the texture features from a Brain Cancer affected MRI. A computer based diagnosis is performed in order to detect the tumors from given Magnetic Resonance Image. Basic image processing techniques are used to locate the tumor region. Basic techniques consist of image enhancement, image bianarization, and image morphological operations. Texture features are computed using the Gray Level Co-occurrence Matrix. Texture features consists of five distinct features. Selective features or the combination of selective features will be used in the future to determine the class of the query image. Astrocytoma type of Brain Cancer affected images are used only for simplicity

  3. Functional brain fluorescence plurimetry in rat by implantable concatenated CMOS imaging system.

    Science.gov (United States)

    Kobayashi, Takuma; Masuda, Hiroyuki; Kitsumoto, Chikara; Haruta, Makito; Motoyama, Mayumi; Ohta, Yasumi; Noda, Toshihiko; Sasagawa, Kiyotaka; Tokuda, Takashi; Shiosaka, Sadao; Ohta, Jun

    2014-03-15

    Measurement of brain activity in multiple areas simultaneously by minimally invasive methods contributes to the study of neuroscience and development of brain machine interfaces. However, this requires compact wearable instruments that do not inhibit natural movements. Application of optical potentiometry with voltage-sensitive fluorescent dye using an implantable image sensor is also useful. However, the increasing number of leads required for the multiple wired sensors to measure larger domains inhibits natural behavior. For imaging broad areas by numerous sensors without excessive wiring, a web-like sensor that can wrap the brain was developed. Kaleidoscopic potentiometry is possible using the imaging system with concatenated sensors by changing the alignment of the sensors. This paper describes organization of the system, evaluation of the system by a fluorescence imaging, and finally, functional brain fluorescence plurimetry by the sensor. The recorded data in rat somatosensory cortex using the developed multiple-area imaging system compared well with electrophysiology results.

  4. Visualization and volumetric structures from MR images of the brain

    Energy Technology Data Exchange (ETDEWEB)

    Parvin, B.; Johnston, W.; Robertson, D.

    1994-03-01

    Pinta is a system for segmentation and visualization of anatomical structures obtained from serial sections reconstructed from magnetic resonance imaging. The system approaches the segmentation problem by assigning each volumetric region to an anatomical structure. This is accomplished by satisfying constraints at the pixel level, slice level, and volumetric level. Each slice is represented by an attributed graph, where nodes correspond to regions and links correspond to the relations between regions. These regions are obtained by grouping pixels based on similarity and proximity. The slice level attributed graphs are then coerced to form a volumetric attributed graph, where volumetric consistency can be verified. The main novelty of our approach is in the use of the volumetric graph to ensure consistency from symbolic representations obtained from individual slices. In this fashion, the system allows errors to be made at the slice level, yet removes them when the volumetric consistency cannot be verified. Once the segmentation is complete, the 3D surfaces of the brain can be constructed and visualized.

  5. ROLE OF MAGNETIC RESONANCE IMAGING BRAIN IN EVALUATION OF SEIZURES

    Directory of Open Access Journals (Sweden)

    Athira

    2015-09-01

    Full Text Available BACKGROUND AND OBJECTIVES: In patients with seizures a dedicated MRI protocol is a useful tool in the detection of an epileptogenic focus, including congenital, neoplastic and degenerative. Resection of these lesions can lead to seizure freedom in most patients. In this context, a prospective study was conducted to evaluate the etiology of seizures using MRI brain. METHODOLOGY: 120 patients presenting with seizures, above the age of 2years, referred to the Department of Radio - diagnosis were included in this study. RESULTS: In this study, the MR examination revealed pathological findi ngs i n 32.50% (39 out of 120 patients which includes: mesial temporal sclerosis - 14.2% (17, cerebral infarct with gliosis - 6.6% (8, meningioma - 2.5% (3, hypoxic ischemic encephalopathy - 1.6% (2, cortical dysplasia - 1.6% (2, tuberous sclerosis - 11.6% (2, nodula r heterotopias - 0.83% (1, neurocysticercosis - 0.83% (1%, metastasis - 0.83% (1, Dyke Davidoff Maison syndrome - 0.83% (1 and Arnold Chiari Malformation 0.83% (1. CONCLUSION: This study concludes that MR imaging plays a pivotal role in the evaluation of pati ents with seizures using a dedicated MRI seizure protocol to confirm or rule out any organic or developmental lesions. The most common abnormality seen in this study was mesial temporal sclerosis.

  6. Dopamine-containing gadolinium complex as magnetic resonance imaging contrast agent

    Institute of Scientific and Technical Information of China (English)

    ZHOU Xin; ZHAO Qi; YANG Lian; YAN Guoping; XU Wei; ZHOU Chengkai; ZHANG Qiao; LI Liang; LIU Fan; GUO Junfang

    2012-01-01

    Gadolinium diethylenetriamine-pentaacetic bisdopamide (Gd-DTPA-2DA) was synthesized by the incorporation of dopamine to diethylenetriaminepentaacetic acid (DTPA) and further reaction with gadolinium chloride.In vitro and in vivo properties were also evaluated.Gadolinium complex Gd-DTPA-2DA possessed higher relaxation effectiveness and less cytotoxicity to HeLa cells than that of Gd-DTPA.Moreover,Gd-DTPA-2DA greatly enhanced the contrast of MR images of the brains,provided prolonged intravascular duration,and produced highly contrasted visualization of the brain.

  7. X-ray Scatter Imaging of Hepatocellular Carcinoma in a Mouse Model Using Nanoparticle Contrast Agents

    Science.gov (United States)

    Rand, Danielle; Derdak, Zoltan; Carlson, Rolf; Wands, Jack R.; Rose-Petruck, Christoph

    2015-10-01

    Hepatocellular carcinoma (HCC) is one of the most common malignant tumors worldwide and is almost uniformly fatal. Current methods of detection include ultrasound examination and imaging by CT scan or MRI; however, these techniques are problematic in terms of sensitivity and specificity, and the detection of early tumors (contrast agents can be detected using SFHI. We also demonstrate that directed targeting and SFHI of HCC tumors in a mouse model is possible through the use of HCC-specific antibodies. The enhanced sensitivity of SFHI relative to currently available techniques enables the x-ray imaging of tumors that are just a few millimeters in diameter and substantially reduces the amount of nanoparticle contrast agent required for intravenous injection relative to absorption-based x-ray imaging.

  8. CMOS Image Sensor and System for Imaging Hemodynamic Changes in Response to Deep Brain Stimulation.

    Science.gov (United States)

    Zhang, Xiao; Noor, Muhammad S; McCracken, Clinton B; Kiss, Zelma H T; Yadid-Pecht, Orly; Murari, Kartikeya

    2016-06-01

    Deep brain stimulation (DBS) is a therapeutic intervention used for a variety of neurological and psychiatric disorders, but its mechanism of action is not well understood. It is known that DBS modulates neural activity which changes metabolic demands and thus the cerebral circulation state. However, it is unclear whether there are correlations between electrophysiological, hemodynamic and behavioral changes and whether they have any implications for clinical benefits. In order to investigate these questions, we present a miniaturized system for spectroscopic imaging of brain hemodynamics. The system consists of a 144 ×144, [Formula: see text] pixel pitch, high-sensitivity, analog-output CMOS imager fabricated in a standard 0.35 μm CMOS process, along with a miniaturized imaging system comprising illumination, focusing, analog-to-digital conversion and μSD card based data storage. This enables stand alone operation without a computer, nor electrical or fiberoptic tethers. To achieve high sensitivity, the pixel uses a capacitive transimpedance amplifier (CTIA). The nMOS transistors are in the pixel while pMOS transistors are column-parallel, resulting in a fill factor (FF) of 26%. Running at 60 fps and exposed to 470 nm light, the CMOS imager has a minimum detectable intensity of 2.3 nW/cm(2) , a maximum signal-to-noise ratio (SNR) of 49 dB at 2.45 μW/cm(2) leading to a dynamic range (DR) of 61 dB while consuming 167 μA from a 3.3 V supply. In anesthetized rats, the system was able to detect temporal, spatial and spectral hemodynamic changes in response to DBS.

  9. Quantitative PET imaging with the 3T MR-BrainPET

    Energy Technology Data Exchange (ETDEWEB)

    Weirich, C., E-mail: c.weirich@fz-juelich.de [Forschungszentrum Jülich, Institute of Neuroscience and Medicine – 4, Juelich (Germany); Scheins, J.; Lohmann, P.; Tellmann, L. [Forschungszentrum Jülich, Institute of Neuroscience and Medicine – 4, Juelich (Germany); Byars, L.; Michel, C. [Siemens Healthcare, Molecular Imaging, Knoxville, TN (United States); Rota Kops, E.; Brenner, D.; Herzog, H.; Shah, N.J. [Forschungszentrum Jülich, Institute of Neuroscience and Medicine – 4, Juelich (Germany)

    2013-02-21

    The new hybrid imaging technology of MR-PET allows for simultaneous acquisition of versatile MRI contrasts and the quantitative metabolic imaging with PET. In order to achieve the quantification of PET images with minimal residual error the application of several corrections is crucial. In this work we present our results on quantification with the 3T MR BrainPET scanner.

  10. Image-guided microbeam irradiation to brain tumour bearing mice using a carbon nanotube x-ray source array

    Science.gov (United States)

    Zhang, Lei; Yuan, Hong; Burk, Laurel M.; Inscoe, Christy R.; Hadsell, Michael J.; Chtcheprov, Pavel; Lee, Yueh Z.; Lu, Jianping; Chang, Sha; Zhou, Otto

    2014-03-01

    Microbeam radiation therapy (MRT) is a promising experimental and preclinical radiotherapy method for cancer treatment. Synchrotron based MRT experiments have shown that spatially fractionated microbeam radiation has the unique capability of preferentially eradicating tumour cells while sparing normal tissue in brain tumour bearing animal models. We recently demonstrated the feasibility of generating orthovoltage microbeam radiation with an adjustable microbeam width using a carbon nanotube based x-ray source array. Here we report the preliminary results from our efforts in developing an image guidance procedure for the targeted delivery of the narrow microbeams to the small tumour region in the mouse brain. Magnetic resonance imaging was used for tumour identification, and on-board x-ray radiography was used for imaging of landmarks without contrast agents. The two images were aligned using 2D rigid body image registration to determine the relative position of the tumour with respect to a landmark. The targeting accuracy and consistency were evaluated by first irradiating a group of mice inoculated with U87 human glioma brain tumours using the present protocol and then determining the locations of the microbeam radiation tracks using γ-H2AX immunofluorescence staining. The histology results showed that among 14 mice irradiated, 11 received the prescribed number of microbeams on the targeted tumour, with an average localization accuracy of 454 µm measured directly from the histology (537 µm if measured from the registered histological images). Two mice received one of the three prescribed microbeams on the tumour site. One mouse was excluded from the analysis due to tissue staining errors.

  11. 3D multi-object segmentation of cardiac MSCT imaging by using a multi-agent approach.

    Science.gov (United States)

    Fleureau, Julien; Garreau, Mireille; Boulmier, Dominique; Hernández, Alfredo

    2007-01-01

    We propose a new technique for general purpose, semi-interactive and multi-object segmentation in N-dimensional images, applied to the extraction of cardiac structures in MultiSlice Computed Tomography (MSCT) imaging. The proposed approach makes use of a multi-agent scheme combined with a supervised classification methodology allowing the introduction of a priori information and presenting fast computing times. The multi-agent system is organised around a communicating agent which manages a population of situated agents which segment the image through cooperative and competitive interactions. The proposed technique has been tested on several patient data sets. Some typical results are finally presented and discussed.

  12. Identification of chronic myocardial infarction with extracellular or intravascular contrast agents in magnetic resonance imaging

    Institute of Scientific and Technical Information of China (English)

    Jian WANG; Hong-yu LIU; Hang L(U); Bo XIANG; Marco GRUWEL; Boguslaw TOMANEK; Roxanne DESLAURIERS; Gang-hong TIAN

    2008-01-01

    Aim: To determine whether extracellular or intravascular contrast agents could detect chronic scarred myocardium in magnetic resonance imaging (MRI). Methods: Eighteen pigs underwent a 4 week ligation of 1 or 2 diagonal coronary arteries to induce chronic myocardial infarction. The hearts were then removed and perfused in a Langendorff apparatus. Eighteen hearts were divided into 2 groups. The hearts in groups Ⅰ (n=9) and Ⅱ (n=9) 收稿日期the bolus injection of Gadolinium diethylenetriamine pentaacetic acid (Gd-DTPA, 0.05 mmol/kg) and ga-dolinium-based macromolecular agent (P792, 15 μmol/kg), respectively. First pass T2* MRI was acquired using a FLASH sequence. Delayed enhancement T1 MRI was acquired with an inversion recovery prepared TurboFLASH sequence.Results: Wash-in of both agents resulted in a sharp and dramatic T2* signal loss of scarred myocardium similar to that of normal myocardium. The magnitude and velocity of T2* signal recovery caused by wash-out of extracellular agents in normal myocardium was significantly less than that in scarred myocardium. Conversely, the T2* signal of scarred and normal myocardium recovered to plateau rapidly and simultaneously due to wash-out of intravascular agents. At the fol-lowing equilibrium, extracellular agent-enhanced T1 signal intensity was signifi-cantly greater in scarred myocardium than in normal myocardium, whereas there was no significantly statistical difference in intravascular agent-enhanced T1 sig-nal intensity between scarred and normal myocardium. Conclusion: After admin-istration of extracellular agents, wash-out T2* first-pass and delayed enhanced T1 MRI could identify scarred myocardium as a hyperenhanced region. Conversely, scarred myocardium was indistinguishable from normal myocardium during first-pass and the steady state of intravascular agents.

  13. Differential structured illumination microendoscopy for in vivo imaging of molecular contrast agents

    Science.gov (United States)

    Keahey, Pelham; Ramalingam, Preetha; Schmeler, Kathleen

    2016-01-01

    Fiber optic microendoscopy has shown promise for visualization of molecular contrast agents used to study disease in vivo. However, fiber optic microendoscopes have limited optical sectioning capability, and image contrast is limited by out-of-focus light generated in highly scattering tissue. Optical sectioning techniques have been used in microendoscopes to remove out-of-focus light but reduce imaging speed or rely on bulky optical elements that prevent in vivo imaging. Here, we present differential structured illumination microendoscopy (DSIMe), a fiber optic system that can perform structured illumination in real time for optical sectioning without any opto-mechanical components attached to the distal tip of the fiber bundle. We demonstrate the use of DSIMe during in vivo fluorescence imaging in patients undergoing surgery for cervical adenocarcinoma in situ. Images acquired using DSIMe show greater contrast than standard microendoscopy, improving the ability to detect cellular atypia associated with neoplasia. PMID:27621464

  14. Development of image-processing software for automatic segmentation of brain tumors in MR images

    Directory of Open Access Journals (Sweden)

    C Vijayakumar

    2011-01-01

    Full Text Available Most of the commercially available software for brain tumor segmentation have limited functionality and frequently lack the careful validation that is required for clinical studies. We have developed an image-analysis software package called ′Prometheus,′ which performs neural system-based segmentation operations on MR images using pre-trained information. The software also has the capability to improve its segmentation performance by using the training module of the neural system. The aim of this article is to present the design and modules of this software. The segmentation module of Prometheus can be used primarily for image analysis in MR images. Prometheus was validated against manual segmentation by a radiologist and its mean sensitivity and specificity was found to be 85.71±4.89% and 93.2±2.87%, respectively. Similarly, the mean segmentation accuracy and mean correspondence ratio was found to be 92.35±3.37% and 0.78±0.046, respectively.

  15. Real-time functional near-infrared imager and imaging of human brain activity

    Science.gov (United States)

    Luo, Qingming; Zeng, Shaoqun; Gong, Hui; Chen, Weiguo; Zhang, Zhi; Chance, Britton

    1999-02-01

    A real time functional near infrared imager (fNIRI) was introduced. The imager was controlled by a computer and the signals from the detectors were converted and processed in real time. A user-friendly software was programmed with Visual C++ language. Relative changes of oxy - Hb, Hb, and total blood concentration in 16 channels and the corresponding images can be displayed in real time on the computer. The imager was used as a real time monitor in psychological tests to record the response of the frontal cortex of human subjects. In mental work and pattern recognition tests, we recorded oxygen consumption and blood flow changes of volunteers' frontal cortex. The psychological results showed that the lower part of the left frontal gyres had intensive relation to pattern recognition and has definite boundaries. However, the mental work involved more zones of the frontal gyres and may be a complex conceptual model. The results also suggested that the human brain has an precise and complicated adjustability. The oxygen supplement in the stimulated area increased as the neuron stimulation.

  16. Antibodies targeted to the brain with image-guided focused ultrasound reduces amyloid-beta plaque load in the TgCRND8 mouse model of Alzheimer's disease.

    Directory of Open Access Journals (Sweden)

    Jessica F Jordão

    Full Text Available Immunotherapy for Alzheimer's disease (AD relies on antibodies directed against toxic amyloid-beta peptide (Abeta, which circulate in the bloodstream and remove Abeta from the brain. In mouse models of AD, the administration of anti-Abeta antibodies directly into the brain, in comparison to the bloodstream, was shown to be more efficient at reducing Abeta plaque pathology. Therefore, delivering anti-Abeta antibodies to the brain of AD patients may also improve treatment efficiency. Transcranial focused ultrasound (FUS is known to transiently-enhance the permeability of the blood-brain barrier (BBB, allowing intravenously administered therapeutics to enter the brain. Our goal was to establish that anti-Abeta antibodies delivered to the brain using magnetic resonance imaging-guided FUS (MRIgFUS can reduce plaque pathology. To test this, TgCRND8 mice received intravenous injections of MRI and FUS contrast agents, as well as anti-Abeta antibody, BAM-10. MRIgFUS was then applied transcranially. Within minutes, the MRI contrast agent entered the brain, and BAM-10 was later found bound to Abeta plaques in targeted cortical areas. Four days post-treatment, Abeta pathology was significantly reduced in TgCRND8 mice. In conclusion, this is the first report to demonstrate that MRIgFUS delivery of anti-Abeta antibodies provides the combined advantages of using a low dose of antibody and rapidly reducing plaque pathology.

  17. Reformatted images improve the detection rate of acute traumatic subdural hematomas on brain CT compared with axial images alone.

    Science.gov (United States)

    Amrhein, Timothy J; Mostertz, William; Matheus, Maria Gisele; Maass-Bolles, Genevieve; Sharma, Komal; Collins, Heather R; Kranz, Peter G

    2017-02-01

    Subdural hematomas (SDHs) comprise a significant percentage of missed intracranial hemorrhage on axial brain CT. SDH detection rates could be improved with the addition of reformatted images. Though performed at some centers, the potential additional diagnostic sensitivity of reformatted images has not yet been investigated. The purpose of our study is to determine if the addition of coronal and sagittal reformatted images to an axial brain CT increases the sensitivity and specificity for detection of acute traumatic SDH. We retrospectively reviewed consecutive brain CTs acquired for acute trauma that contained new SDHs. An equivalent number of normal brain CTs served as control. Paired sets of images were created for each case: (1) axial images only ("axial only") and (2) axial, coronal, sagittal images ("reformat added"). Three readers interpreted both the axial only and companion reformat added for each case, separated by 1 month. Reading times and SDH detection rates were compared. One hundred SDH and 100 negative examinations were collected. Sensitivity and specificity for the axial-only scans were 75.7 and 94.3 %, respectively, compared with 88.3 and 98.3 % for reformat added. There was a 24.3 % false negative (missed SDH) rate with axial-only scans versus 11.7 % with reformat added (p = negatives by greater than 50 %. Reformatted images substantially reduce the number of missed SDHs compared with axial images alone.

  18. Evaluation of a targeted nanobubble ultrasound contrast agent for potential tumor imaging

    Science.gov (United States)

    Li, Chunfang; Shen, Chunxu; Liu, Haijuan; Wu, Kaizhi; Zhou, Qibing; Ding, Mingyue

    2015-03-01

    Targeted nanobubbles have been reported to improve the contrast effect of ultrasound imaging due to the enhanced permeation and retention effects at tumor vascular leaks. In this work, the contrast enhancement abilities and the tumor targeting potential of a self-made VEGFR2-targeted nanobubble ultrasound contrast agent was evaluated in-vitro and in-vivo. Size distribution and zeta potential were assessed. Then the contrast-enhanced ultrasound imaging of the VEGFR2 targeted nanobubbles were evaluated with a custom-made experimental apparatus and in normal Wistar rats. Finally, the in-vivo tumor-targeting ability was evaluated on nude mice with subcutaneous tumor. The results showed that the target nanobubbles had uniform distribution with the average diameter of 208.1 nm, polydispersity index (PDI) of 0.411, and zeta potential of -13.21 mV. Significant contrast enhancement was observed in both in-vitro and in-vivo ultrasound imaging, demonstrating that the self-made target nanobubbles can enhance the contrast effect of ultrasound imaging efficiently. Targeted tumor imaging showed less promising result, due to the fact that the targeted nanobubbles arriving and permeating through tumor vessels were not many enough to produce significant enhancement. Future work will focus on exploring new imaging algorithm which is sensitive to targeted nanobubbles, so as to correctly detect the contrast agent, particularly at a low bubble concentration.

  19. Experimental design and instability analysis of coaxial electrospray process for microencapsulation of drugs and imaging agents.

    Science.gov (United States)

    Si, Ting; Zhang, Leilei; Li, Guangbin; Roberts, Cynthia J; Yin, Xiezhen; Xu, Ronald

    2013-07-01

    Recent developments in multimodal imaging and image-guided therapy requires multilayered microparticles that encapsulate several imaging and therapeutic agents in the same carrier. However, commonly used microencapsulation processes have multiple limitations such as low encapsulation efficiency and loss of bioactivity for the encapsulated biological cargos. To overcome these limitations, we have carried out both experimental and theoretical studies on coaxial electrospray of multilayered microparticles. On the experimental side, an improved coaxial electrospray setup has been developed. A customized coaxial needle assembly combined with two ring electrodes has been used to enhance the stability of the cone and widen the process parameter range of the stable cone-jet mode. With this assembly, we have obtained poly(lactide-co-glycolide) microparticles with fine morphology and uniform size distribution. On the theoretical side, an instability analysis of the coaxial electrified jet has been performed based on the experimental parameters. The effects of process parameters on the formation of different unstable modes have been studied. The reported experimental and theoretical research represents a significant step toward quantitative control and optimization of the coaxial electrospray process for microencapsulation of multiple drugs and imaging agents in multimodal imaging and image-guided therapy.

  20. A Review of Fully Automated Techniques for Brain Tumor Detection From MR Images

    Directory of Open Access Journals (Sweden)

    Anjum Hayat Gondal

    2013-02-01

    Full Text Available Radiologists use medical images to diagnose diseases precisely. However, identification of brain tumor from medical images is still a critical and complicated job for a radiologist. Brain tumor identification form magnetic resonance imaging (MRI consists of several stages. Segmentation is known to be an essential step in medical imaging classification and analysis. Performing the brain MR images segmentation manually is a difficult task as there are several challenges associated with it. Radiologist and medical experts spend plenty of time for manually segmenting brain MR images, and this is a non-repeatable task. In view of this, an automatic segmentation of brain MR images is needed to correctly segment White Matter (WM, Gray Matter (GM and Cerebrospinal Fluid (CSF tissues of brain in a shorter span of time. The accurate segmentation is crucial as otherwise the wrong identification of disease can lead to severe consequences. Taking into account the aforesaid challenges, this research is focused towards highlighting the strengths and limitations of the earlier proposed segmentation techniques discussed in the contemporary literature. Besides summarizing the literature, the paper also provides a critical evaluation of the surveyed literature which reveals new facets of research. However, articulating a new technique is beyond the scope of this paper.

  1. Blood-brain barrier permeability imaging using perfusion computed tomography

    Directory of Open Access Journals (Sweden)

    Avsenik Jernej

    2015-06-01

    Full Text Available Background. The blood-brain barrier represents the selective diffusion barrier at the level of the cerebral microvascular endothelium. Other functions of blood-brain barrier include transport, signaling and osmoregulation. Endothelial cells interact with surrounding astrocytes, pericytes and neurons. These interactions are crucial to the development, structural integrity and function of the cerebral microvascular endothelium. Dysfunctional blood-brain barrier has been associated with pathologies such as acute stroke, tumors, inflammatory and neurodegenerative diseases.

  2. Blood-brain barrier permeability imaging using perfusion computed tomography

    OpenAIRE

    Avsenik Jernej; Bisdas Sotirios; Popovic Katarina Surlan

    2015-01-01

    Background. The blood-brain barrier represents the selective diffusion barrier at the level of the cerebral microvascular endothelium. Other functions of blood-brain barrier include transport, signaling and osmoregulation. Endothelial cells interact with surrounding astrocytes, pericytes and neurons. These interactions are crucial to the development, structural integrity and function of the cerebral microvascular endothelium. Dysfunctional blood-brain barrier has been associated with patholog...

  3. Comparison of heterogeneity quantification algorithms for brain SPECT perfusion images

    OpenAIRE

    Modzelewski, Romain; Janvresse, Elise; De La Rue, Thierry; Vera, Pierre

    2012-01-01

    Background Several algorithms from the literature were compared with the original random walk (RW) algorithm for brain perfusion heterogeneity quantification purposes. Algorithms are compared on a set of 210 brain single photon emission computed tomography (SPECT) simulations and 40 patient exams. Methods Five algorithms were tested on numerical phantoms. The numerical anthropomorphic Zubal head phantom was used to generate 42 (6 × 7) different brain SPECT simulations. Seven diffuse cortical ...

  4. Clinical experience with technetium-99m teboroxime, a neutral, lipophilic myocardial perfusion imaging agent

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, L.L.; Seldin, D.W. (Columbia Univ., New York, NY (USA))

    1990-10-16

    Technetium-99m (Tc-99m) teboroxime is a new technetium-based myocardial perfusion imaging agent (investigational code = SQ30217 (Cardiotec, Squibb Diagnostics)). A member of a class of neutral, lipophilic, technetium-containing complexes known as boronic acid adducts of technetium dioxime (BATO) complexes, this agent is chemically very different from the cationic tracer thallium-201 (Tl-201) and from the cationic technetium complex Tc-99m sestamibi (Cardiolite, Du Pont Imaging Agents). Tc-99m teboroxime has high myocardial extraction, rapid blood clearance, little lung uptake and rapid myocardial washout. A biexponential pattern of myocardial washout is demonstrated in animals and in man. Effective half-lives of the 2 washout components in man are 5.2 minutes and 3.8 hours and represent approximately 66 and 33% of the myocardial activity, respectively. The first half-life for the myocardium is approximately 11 minutes. As the agent washes out of the heart, hepatic uptake occurs, peaking at about 5 minutes after injection. The liver is the major organ of excretion and receives, along with the large bowel, the largest radiation dose. Rapid imaging protocols using standard cameras have achieved good myocardial counts from 3 planar views acquired over a 4- to 5-minute period or for single photon emission computed tomography (SPECT) images acquired over a 10-minute period. An entire stress/rest procedure can be completed in 1 hour. Analysis of data from 155 patients from 4 centers using planar or SPECT imaging showed a sensitivity and specificity for blinded readings of 82 and 91%, respectively, when compared against overall clinical impression. 13 references.

  5. Dual-wavelength laser speckle imaging for monitoring brain metabolic and hemodynamic response to closed head traumatic brain injury in mice

    Science.gov (United States)

    Kofman, Itamar; Abookasis, David

    2015-10-01

    The measurement of dynamic changes in brain hemodynamic and metabolism events following head trauma could be valuable for injury prognosis and for planning of optimal medical treatment. Specifically, variations in blood flow and oxygenation levels serve as important biomarkers of numerous pathophysiological processes. We employed the dual-wavelength laser speckle imaging (DW-LSI) technique for simultaneous monitoring of changes in brain hemodynamics and cerebral blood flow (CBF) at early stages of head trauma in a mouse model of intact head injury (n=10). For induction of head injury, we used a weight-drop device involving a metal mass (˜50 g) striking the mouse's head in a regulated manner from a height of ˜90 cm. In comparison to baseline measurements, noticeable dynamic variations were revealed immediately and up to 1 h postinjury, which indicate the severity of brain damage and highlight the ability of the DW-LSI arrangement to track brain pathophysiology induced by injury. To validate the monitoring of CBF by DW-LSI, measurements with laser Doppler flowmetry (LDF) were also performed (n=5), which confirmed reduction in CBF following injury. A secondary focus of the study was to investigate the effectiveness of hypertonic saline as a neuroprotective agent, inhibiting the development of complications after brain injury in a subgroup of injured mice (n=5), further demonstrating the ability of DW-LSI to monitor the effects upon brain dynamics of drug treatment. Overall, our findings further support the use of DW-LSI as a noninvasive, cost-effective tool to assess changes in hemodynamics under a variety of pathological conditions, suggesting its potential contribution to the biomedical field. To the best of our knowledge, this work is the first to make use of the DW-LSI modality in a small animal model to (1) investigate brain function during the critical first hour of closed head injury trauma, (2) correlate between injury parameters of LDF measurements, and (3

  6. 1.5 Harmonic Imaging Sonography with microbubble contrast agent improves characterization of hepatocellular carcinoma

    Institute of Scientific and Technical Information of China (English)

    Kouji Yamamoto; Katsuya Shiraki; Shigeo Nakanishi; Hiroyuki Fuke; Takeshi Nakano; Akira Hashimoto; Atsuya Shimizu; Toshinobu Hamataki

    2005-01-01

    AIM: To investigate the usefulness of 1.5 Harmonic Imaging Sonography with the use of the contrast agent Levovist for the diagnosis of hepatocellular carcinoma (HCC) and for the evaluation of therapeutic response.METHODS: Phantom experiments were performed to compare the contrast effects of 2nd harmonic imaging and 1.5 Harmonic Imaging Sonography. 1.5 Harmonic Imaging Sonography was employed to examine 36 patients with HCC (42 nodules) before and after the treatment and to compare against the findings obtained using other diagnostic imaging modalities. RESULTS: In 1.5 Harmonic Imaging Sonography, the tumor vessels of HCCs were clearly identified during the early phase, and late-phase images clearly demonstrated the differences in contrast enhancement between the tumor and surrounding hepatic parenchyma. Blood flow within the tumor was detected in 36 nodules (85.7%)during the early phase and in all 42 nodules (100%) during the late phase using 1.5 Harmonic Imaging Sonography,in 38 nodules (90.5%) using contrast-enhanced CT, in 34nodules (81.0%) using digital subtraction angiography (DSA), and in 42 nodules (100%) using US CO2angiography.Following transcatheter arterial embolization, 1.5Harmonic Imaging Sonography detected blood flow and contrast enhancement within the tumors that were judged to contain viable tissue in 20 of 42 nodules (47.6%).However, 6 of these 20 cases were not judged in contrastenhanced CT. 1.5 Harmonic Imaging Sonography was compared with the US CO2 angiography findings as the gold standard, and the sensitivity and specificity of these images for discerning viable and nonviable HCC after transcatheter arterial embolization were 100% and 100%,respectively.CONCLUSION: 1.5 Harmonic Imaging Sonography permits the vascular structures of HCCs to be identified and blood flow within the tumor to be clearly demonstrated.Furthermore, 1.5 Harmonic Imaging Sonography is potentially useful for evaluating the therapeutic effects of transcatheter arterial

  7. The Iconographic Brain.A critical philosophical inquiry into (the resistance of the image.

    Directory of Open Access Journals (Sweden)

    Jan eDe Vos

    2014-05-01

    Full Text Available The brain image plays a central role in contemporary image culture and, in turn, (coconstructs contemporary forms of subjectivity. The central aim of this paper is to probe the unmistakably potent interpellative power of brain images by delving into the power of imaging and the power of the image itself. This is not without relevance for the neurosciences, inasmuch as these do not take place in a vacuum; hence the importance of inquiring into the status of the image within scientific culture and science itself.I will mount a critical philosophical investigation of the brain qua image, focusing on the issue of mapping the mental onto the brain and how, in turn, the brain image plays a pivotal role in processes of subjectivation. Hereto, I draw upon Science & Technology Studies, juxtaposed with culture and ideology critique and theories of image culture.The first section sets out from Althusser’s concept of interpellation, linking ideology to subjectivity. Doing so allows to spell out the central question of the paper: what could serve as the basis for a critical approach, or, where can a locus of resistance be found? In the second section, drawing predominantly on Baudrillard, I delve into the dimension of virtuality as this is opened up by brain image culture. This leads to the question of whether the digital brain must be opposed to old analog psychology: is it the psyche which resists? This issue is taken up in the third section which, ultimately, concludes that the psychological is not the requisite locus of resistance. The fourth section proceeds to delineate how the brain image is constructed from what I call the data-gaze (the claim that brain data are always already visual. In the final section, I discuss how an engagement with theories of iconology affords a critical understanding of the interpellative force of the brain image, which culminates in the somewhat unexpected claim that the sought after resistance lies in the very status of

  8. Brain tissue segmentation in PET-CT images using probabilistic atlas and variational Bayes inference.

    Science.gov (United States)

    Xia, Yong; Wang, Jiabin; Eberl, Stefan; Fulham, Michael; Feng, David Dagan

    2011-01-01

    PET-CT provides aligned anatomical (CT) and functional (PET) images in a single scan, and has the potential to improve brain PET image segmentation, which can in turn improve quantitative clinical analyses. We propose a statistical segmentation algorithm that incorporates the prior anatomical knowledge represented by probabilistic brain atlas into the variational Bayes inference to delineate gray matter (GM), white matter (WM) and cerebrospinal fluid (CSF) in brain PET-CT images. Our approach adds an additional novel aspect by allowing voxels to have variable and adaptive prior probabilities of belonging to each class. We compared our algorithm to the segmentation approaches implemented in the expectation maximization segmentation (EMS) and statistical parametric mapping (SPM8) packages in 26 clinical cases. The results show that our algorithm improves the accuracy of brain PET-CT image segmentation.

  9. Clinical application of brain imaging for the diagnosis of mood disorders: the current state of play.

    Science.gov (United States)

    Savitz, J B; Rauch, S L; Drevets, W C

    2013-05-01

    In response to queries about whether brain imaging technology has reached the point where it is useful for making a clinical diagnosis and for helping to guide treatment selection, the American Psychiatric Association (APA) has recently written a position paper on the Clinical Application of Brain Imaging in Psychiatry. The following perspective piece is based on our contribution to this APA position paper, which specifically emphasized the application of neuroimaging in mood disorders. We present an introductory overview of the challenges faced by researchers in developing valid and reliable biomarkers for psychiatric disorders, followed by a synopsis of the extant neuroimaging findings in mood disorders, and an evidence-based review of the current research on brain imaging biomarkers in adult mood disorders. Although there are a number of promising results, by the standards proposed below, we argue that there are currently no brain imaging biomarkers that are clinically useful for establishing diagnosis or predicting treatment outcome in mood disorders.

  10. Advanced techniques in magnetic resonance imaging of the brain in children with ADHD

    Energy Technology Data Exchange (ETDEWEB)

    Pastura, Giuseppe, E-mail: giuseppe.pastura@terra.com.b [Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ (Brazil). Instituto de Puericultura e Pediatria Martagao Gesteira. Dept. de Pediatria; Mattos, Paulo [Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ (Brazil). Instituto de Puericultura e Pediatria Martagao Gesteira. Dept. de Psiquiatria; Gasparetto, Emerson Leandro [Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ (Brazil). Instituto de Puericultura e Pediatria Martagao Gesteira. Dept. de Radiologia; Araujo, Alexandra Prufer de Queiroz Campos [Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ (Brazil). Instituto de Puericultura e Pediatria Martagao Gesteira. Dept. de Neuropediatria

    2011-04-15

    Attention deficit hyperactivity disorder (ADHD) affects about 5% of school-aged child. Previous published works using different techniques of magnetic resonance imaging (MRI) have demonstrated that there may be some differences between the brain of people with and without this condition. This review aims at providing neurologists, pediatricians and psychiatrists an update on the differences between the brain of children with and without ADHD using advanced techniques of magnetic resonance imaging such as diffusion tensor imaging, brain volumetry and cortical thickness, spectroscopy and functional MRI. Data was obtained by a comprehensive, non-systematic review of medical literature. The regions with a greater number of abnormalities are splenium of the corpus callosum, cingulated gyrus, caudate nucleus, cerebellum, striatum, frontal and temporal cortices. The brain regions where abnormalities are observed in studies of diffusion tensor, volumetry, spectroscopy and cortical thickness are the same involved in neurobiological theories of ADHD coming from studies with functional magnetic resonance imaging. (author)

  11. Partial volume effect modeling for segmentation and tissue classification of brain magnetic resonance images: A review.

    Science.gov (United States)

    Tohka, Jussi

    2014-11-28

    Quantitative analysis of magnetic resonance (MR) brain images are facilitated by the development of automated segmentation algorithms. A single image voxel may contain of several types of tissues due to the finite spatial resolution of the imaging device. This phenomenon, termed partial volume effect (PVE), complicates the segmentation process, and, due to the complexity of human brain anatomy, the PVE is an important factor for accurate brain structure quantification. Partial volume estimation refers to a generalized segmentation task where the amount of each tissue type within each voxel is solved. This review aims to provide a systematic, tutorial-like overview and categorization of methods for partial volume estimation in brain MRI. The review concentrates on the statistically based approaches for partial volume estimation and also explains differences to other, similar image segmentation approaches.

  12. Brain functional magnetic resonance imaging response to glucose and fructose infusions in humans

    Science.gov (United States)

    Objective: In animals, intracerebroventricular glucose and fructose have opposing effects on appetite and weight regulation. In humans, functional brain magnetic resonance imaging (fMRI) studies during carbohydrate ingestion suggest that glucose may regulate HT signaling but are potentially confoun...

  13. Dual Language Use in Sign-Speech Bimodal Bilinguals: fNIRS Brain-Imaging Evidence

    Science.gov (United States)

    Kovelman, Ioulia; Shalinsky, Mark H.; White, Katherine S.; Schmitt, Shawn N.; Berens, Melody S.; Paymer, Nora; Petitto, Laura-Ann

    2009-01-01

    The brain basis of bilinguals' ability to use two languages at the same time has been a hotly debated topic. On the one hand, behavioral research has suggested that bilingual dual language use involves complex and highly principled linguistic processes. On the other hand, brain-imaging research has revealed that bilingual language switching…

  14. Localization and labeling of rat brain in MR image based on Paxinos-Watson atlas

    Science.gov (United States)

    Cao, Jie; Cai, Chao; Ding, Mingyue; Zhou, Chengping

    2006-03-01

    Localization and labeling of function regions in brain is an important topic in experimental brain sciences because the huge amount of data collected by neuroscientists will become meaningless if we cannot give them a precise description of their locations. In this paper, we proposed a localization and labelling method of 3D MR image of rat brain based on Paxinos-Watson atlas. Our objective is to use the specific atlas to accomplish localization and labeling of specified tissue of interest (TOI) to mimic a veteran expert such that invisible or unclear anatomic function regions in the MR images of rat brain can be automatically identified and marked. We proposed a multi-step method to locate and label the TOIs from the MR image of rat brain. Firstly, pre-processing. It aims at the digitization and 3D reconstruction of the atlas and MRI of rat brain. Secondly, two-step registration. The global registration is to eliminate the big misalign and section angle offset as well as the scale between the MRI and atlas. We can choose some unambiguous and characteristic points manually, and based on these correspondences a coarse registration is obtained using affine model. The local registration is to address individual variability of rat brain that can be performed by using Snake model. Thirdly, post-processing. The goal is to locate and label the TOIs in the selected MR image of rat brain slice guided by well-registered atlas. The experiments demonstrated the feasibility of our method.

  15. The human sexual response cycle : Brain imaging evidence linking sex to other pleasures

    NARCIS (Netherlands)

    Georgiadis, J. R.; Kringelbach, M. L.

    2012-01-01

    Sexual behavior is critical to species survival, yet comparatively little is known about the neural mechanisms in the human brain. Here we systematically review the existing human brain imaging literature on sexual behavior and show that the functional neuroanatomy of sexual behavior is comparable t

  16. Fully automated rodent brain MR image processing pipeline on a Midas server: from acquired images to region-based statistics.

    Science.gov (United States)

    Budin, Francois; Hoogstoel, Marion; Reynolds, Patrick; Grauer, Michael; O'Leary-Moore, Shonagh K; Oguz, Ipek

    2013-01-01

    Magnetic resonance imaging (MRI) of rodent brains enables study of the development and the integrity of the brain under certain conditions (alcohol, drugs etc.). However, these images are difficult to analyze for biomedical researchers with limited image processing experience. In this paper we present an image processing pipeline running on a Midas server, a web-based data storage system. It is composed of the following steps: rigid registration, skull-stripping, average computation, average parcellation, parcellation propagation to individual subjects, and computation of region-based statistics on each image. The pipeline is easy to configure and requires very little image processing knowledge. We present results obtained by processing a data set using this pipeline and demonstrate how this pipeline can be used to find differences between populations.

  17. Controversies of diffusion weighted imaging in the diagnosis of brain death.

    Science.gov (United States)

    Luchtmann, Michael; Bernarding, Johannes; Beuing, Oliver; Kohl, Jana; Bondar, Imre; Skalej, Martin; Firsching, Raimund

    2013-10-01

    Imaging techniques as confirmatory tests may add safety to the diagnosis of brain death, but are partly not accepted either because they are too invasive, such as conventional arterial angiography, or because there is still lack of evidence of its reliability, such as magnetic resonance angiography. In this study the reliability of diffusion weighted imaging for the diagnosis of brain death was evaluated according in terms of its sensitivity and specificity. The apparent diffusion coefficients (ADC) of 18 brain dead patients were registered from 14 distinct brain areas. The mean ADC values of the brain dead patients were compared with normal controls of physiological ADC values of unaffected brain tissue. Despite a highly significant decrease of the mean ADC value in 16 patients, two patients showed mean ADC values that were within normal physiological range. An explanation may be the pseudonormalization of ADC values seen in stroke patients that depends on the time of the onset of the brain damage. We conclude, diffusion-weighted imaging may provide additional information on damage of the brain tissue but is not a practicable confirmatory test for the reliable diagnosis of brain death.

  18. In vivo high-resolution diffusion tensor imaging of the mouse brain.

    Science.gov (United States)

    Wu, Dan; Xu, Jiadi; McMahon, Michael T; van Zijl, Peter C M; Mori, Susumu; Northington, Frances J; Zhang, Jiangyang

    2013-12-01

    Diffusion tensor imaging (DTI) of the laboratory mouse brain provides important macroscopic information for anatomical characterization of mouse models in basic research. Currently, in vivo DTI of the mouse brain is often limited by the available resolution. In this study, we demonstrate in vivo high-resolution DTI of the mouse brain using a cryogenic probe and a modified diffusion-weighted gradient and spin echo (GRASE) imaging sequence at 11.7 T. Three-dimensional (3D) DTI of the entire mouse brain at 0.125 mm isotropic resolution could be obtained in approximately 2 h. The high spatial resolution, which was previously only available with ex vivo imaging, enabled non-invasive examination of small structures in the adult and neonatal mouse brains. Based on data acquired from eight adult mice, a group-averaged DTI atlas of the in vivo adult mouse brain with 60 structure segmentations was developed. Comparisons between in vivo and ex vivo mouse brain DTI data showed significant differences in brain morphology and tissue contrasts, which indicate the importance of the in vivo DTI-based mouse brain atlas.

  19. Cell tracking with gadophrin-2: a bifunctional contrast agent for MR imaging, optical imaging, and fluorescence microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Daldrup-Link, Heike E. [Department of Radiology, UCSF Medical Center, University of California in San Francisco, 513 Parnassus Ave, CA 94143, San Francisco (United States); Rudelius, Martina; Piontek, Guido; Schlegel, Juergen [Institute of Pathology, Technical University, Munich (Germany); Metz, Stephan; Settles, Marcus; Rummeny, Ernst J. [Department of Radiology, Technical University, Munich (Germany); Pichler, Bernd [Department of Biomedical Engineering, University of California Davis, Davis (United States); Heinzmann, Ulrich [National Research Center for Environment and Health, Technical University, Munich (Germany); Oostendorp, Robert A.J. [3. Clinic of Internal Medicine, Laboratory of Stem Cell Physiology, Technical University, Munich (Germany)

    2004-09-01

    The purpose of this study was to assess the feasibility of use of gadophrin-2 to trace intravenously injected human hematopoietic cells in athymic mice, employing magnetic resonance (MR) imaging, optical imaging (OI), and fluorescence microscopy. Mononuclear peripheral blood cells from GCSF-primed patients were labeled with gadophrin-2 (Schering AG, Berlin, Germany), a paramagnetic and fluorescent metalloporphyrin, using established transfection techniques with cationic liposomes. The labeled cells were evaluated in vitro with electron microscopy and inductively coupled plasma atomic emission spectrometry. Then, 1 x 10{sup 6}-3 x 10{sup 8} labeled cells were injected into 14 nude Balb/c mice and the in vivo cell distribution was evaluated with MR imaging and OI before and 4, 24, and 48 h after intravenous injection (p.i.). Five additional mice served as controls: three mice were untreated controls and two mice were investigated after injection of unlabeled cells. The contrast agent effect was determined quantitatively for MR imaging by calculating signal-to-noise-ratio (SNR) data. After completion of in vivo imaging studies, fluorescence microscopy of excised organs was performed. Intracellular cytoplasmatic uptake of gadophrin-2 was confirmed by electron microscopy. Spectrometry determined an uptake of 31.56 nmol Gd per 10{sup 6} cells. After intravenous injection, the distribution of gadophrin-2 labeled cells in nude mice could be visualized by MR, OI, and fluorescence microscopy. At 4 h p.i., the transplanted cells mainly distributed to lung, liver, and spleen, and 24 h p.i. they also distributed to the bone marrow. Fluorescence microscopy confirmed the distribution of gadophrin-2 labeled cells to these target organs. Gadophrin-2 is suited as a bifunctional contrast agent for MR imaging, OI, and fluorescence microscopy and may be used to combine the advantages of each individual imaging modality for in vivo tracking of intravenously injected hematopoietic cells

  20. Decoding brain responses to pixelized images in the primary visual cortex: implications for visual cortical prostheses.

    Science.gov (United States)

    Guo, Bing-Bing; Zheng, Xiao-Lin; Lu, Zhen-Gang; Wang, Xing; Yin, Zheng-Qin; Hou, Wen-Sheng; Meng, Ming

    2015-10-01

    Visual cortical prostheses have the potential to restore partial vision. Still limited by the low-resolution visual percepts provided by visual cortical prostheses, implant wearers can currently only "see" pixelized images, and how to obtain the specific brain responses to different pixelized images in the primary visual cortex (the implant area) is still unknown. We conducted a functional magnetic resonance imaging experiment on normal human participants to investigate the brain activation patterns in response to 18 different pixelized images. There were 100 voxels in the brain activation pattern that were selected from the primary visual cortex, and voxel size was 4 mm × 4 mm × 4 mm. Multi-voxel pattern analysis was used to test if these 18 different brain activation patterns were specific. We chose a Linear Support Vector Machine (LSVM) as the classifier in this study. The results showed that the classification accuracies of different brain activation patterns were significantly above chance level, which suggests that the classifier can successfully distinguish the brain activation patterns. Our results suggest that the specific brain activation patterns to different pixelized images can be obtained in the primary visual cortex using a 4 mm × 4 mm × 4 mm voxel size and a 100-voxel pattern.